<PAGE> PAGE 1
000 B000000 12/31/98
000 C000000 0000036405
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0.a
000 J000000 U
001 A000000 VANGUARD INDEX FUNDS
001 B000000 811-2652
001 C000000 6106691000
002 A000000 100 VANGUARD BOULEVARD
002 B000000 MALVERN
002 C000000 PA
002 D010000 19355
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 Y
007 B000000 9
007 C010100 1
007 C020100 VANGUARD 500 INDEX FUND
007 C030100 N
007 C010200 2
007 C020200 VANGUARD EXTENDED MARKET INDEX FUND
007 C030200 N
007 C010300 3
007 C020300 VANGUARD TOTAL STOCK MARKET INDEX FUND
007 C030300 N
007 C010400 4
007 C020400 VANGUARD VALUE INDEX FUND
007 C030400 N
007 C010500 5
007 C020500 VANGUARD GROWTH INDEX FUND
007 C030500 N
007 C010600 6
007 C020600 VANGUARD SMALL-CAP INDEX FUND
007 C030600 N
007 C010700 7
007 C020700 VANGUARD MID-CAP INDEX FUND
007 C030700 N
007 C010800 8
007 C020800 VANGUARD SMALL-CAP VALUE INDEX FUND
007 C030800 N
007 C010900 9
007 C020900 VANGUARD SMALL-CAP GROWTH INDEX FUND
007 C030900 N
007 C011000 10
010 A00AA01 THE VANGUARD GROUP, INC.
<PAGE> PAGE 2
010 B00AA01 801-11953
010 C01AA01 MALVERN
010 C02AA01 PA
010 C03AA01 19355
012 A00AA01 THE VANGUARD GROUP, INC.
012 B00AA01 84-772
012 C01AA01 MALVERN
012 C02AA01 PA
012 C03AA01 19355
013 A00AA01 PRICE WATERHOUSE LLP
013 B01AA01 PHILADELPHIA
013 B02AA01 PA
013 B03AA01 19103
014 A00AA01 VANGUARD MARKETING CORPORATION
014 B00AA01 8-21570
018 00AA00 Y
019 A00AA00 Y
019 B00AA00 97
019 C00AA00 VANGUARDGR
020 A000001 INVESTMENT TECHNOLOGY GROUP, INC.
020 B000001 95-4339369
020 C000001 2053
020 A000002 BEAR STEARNS & COS. INC.
020 B000002 13-3299429
020 C000002 1489
020 A000003 SMITH BARNEY INC.
020 B000003 13-1912900
020 C000003 1176
020 A000004 INSTINET CORP.
020 B000004 13-3443395
020 C000004 1128
020 A000005 PAINEWEBBER INC.
020 B000005 13-2638166
020 C000005 899
020 A000006 MORGAN STANLEY & CO., INC.
020 B000006 13-2655998
020 C000006 597
020 A000007 GOLDMAN SACHS & CO.
020 B000007 13-5108880
020 C000007 352
020 A000008 WEEDEN & CO.
020 B000008 13-3364318
020 C000008 270
020 A000009 SBC WARBURG INC.
020 B000009 13-3340045
020 C000009 221
020 A000010 CREDIT SUISSE FIRST BOSTON CORP.
020 B000010 13-5659485
020 C000010 217
021 000000 9244
022 A000001 THE VANGUARD GROUP, INC./POOLED CASH ACCT.
<PAGE> PAGE 3
022 B000001 23-1945930
022 C000001 7922561
022 D000001 8076737
022 A000002 TROSTER SINGER STEVENS ROTHCHILD CORP.
022 B000002 13-5515160
022 C000002 1618823
022 D000002 25115
022 A000003 VANGUARD VALUE INDEX FUND
022 B000003 23-2695173
022 C000003 416034
022 D000003 578837
022 A000004 VANGUARD GROWTH INDEX FUND
022 B000004 23-2695174
022 C000004 571540
022 D000004 355312
022 A000005 VANGUARD INSTITUTIONAL INDEX FUND
022 B000005 23-2601141
022 C000005 450101
022 D000005 172729
022 A000006 MORGAN STANLEY & CO., INC.
022 B000006 13-2655998
022 C000006 537934
022 D000006 2795
022 A000007 GOLDMAN SACHS & CO.
022 B000007 13-5108880
022 C000007 501612
022 D000007 6314
022 A000008 VANGUARD 500 INDEX FUND
022 B000008 23-1999755
022 C000008 26596
022 D000008 344628
022 A000009 VANGUARD EXTENDED MARKET INDEX FUND
022 B000009 23-2482430
022 C000009 258103
022 D000009 28468
022 A000010 SHERWOOD SECURITIES CORP.
022 B000010 13-2616318
022 C000010 101757
022 D000010 76677
023 C000000 13323158
023 D000000 10415845
026 A000000 N
026 B000000 N
026 C000000 N
026 D000000 Y
026 E000000 N
026 F000000 N
026 G010000 N
026 G020000 N
026 H000000 N
027 000000 Y
<PAGE> PAGE 4
029 00AA00 N
030 A00AA00 0
030 B00AA00 0.00
030 C00AA00 0.00
031 A00AA00 0
031 B00AA00 0
032 00AA00 0
033 00AA00 0
034 00AA00 N
035 00AA00 0
036 B00AA00 0
037 00AA00 N
038 00AA00 0
039 00AA00 Y
040 00AA00 N
042 A00AA00 0
042 B00AA00 0
042 C00AA00 0
042 D00AA00 0
042 E00AA00 0
042 F00AA00 0
042 G00AA00 0
042 H00AA00 0
043 00AA00 0
044 00AA00 0
045 00AA00 N
048 00AA00 0.000
048 A01AA00 0
048 A02AA00 0.000
048 B01AA00 0
048 B02AA00 0.000
048 C01AA00 0
048 C02AA00 0.000
048 D01AA00 0
048 D02AA00 0.000
048 E01AA00 0
048 E02AA00 0.000
048 F01AA00 0
048 F02AA00 0.000
048 G01AA00 0
048 G02AA00 0.000
048 H01AA00 0
048 H02AA00 0.000
048 I01AA00 0
048 I02AA00 0.000
048 J01AA00 0
048 J02AA00 0.000
048 K01AA00 0
048 K02AA00 0.000
058 A00AA00 N
059 00AA00 Y
<PAGE> PAGE 5
060 A00AA00 Y
060 B00AA00 Y
061 00AA00 3000
062 A00AA00 N
062 B00AA00 0.0
062 C00AA00 0.0
062 D00AA00 0.0
062 E00AA00 0.0
062 F00AA00 0.0
062 G00AA00 0.0
062 H00AA00 0.0
062 I00AA00 0.0
062 J00AA00 0.0
062 K00AA00 0.0
062 L00AA00 0.0
062 M00AA00 0.0
062 N00AA00 0.0
062 O00AA00 0.0
062 P00AA00 0.0
062 Q00AA00 0.0
062 R00AA00 0.0
063 A00AA00 0
063 B00AA00 0.0
077 A000000 Y
077 B000000 Y
077 C000000 Y
077 D000000 N
077 E000000 N
077 F000000 N
077 G000000 N
077 H000000 N
077 I000000 N
077 J000000 N
077 K000000 N
077 L000000 N
077 M000000 N
077 N000000 N
077 O000000 N
077 P000000 N
077 Q010000 N
077 Q020000 N
077 Q030000 N
078 000000 N
080 A00AA00 ICI MUTUAL INSURANCE COMPANY
080 C00AA00 350000
081 A00AA00 Y
081 B00AA00 174
082 A00AA00 N
082 B00AA00 0
083 A00AA00 N
083 B00AA00 0
<PAGE> PAGE 6
084 A00AA00 N
084 B00AA00 0
085 A00AA00 Y
085 B00AA00 N
086 A010000 0
086 A020000 0
086 B010000 0
086 B020000 0
086 C010000 0
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
015 A000101 STATE STREET BANK AND TRUST COMPANY
015 B000101 C
015 C010101 BOSTON
015 C020101 MA
015 C030101 02110
015 E010101 X
024 000100 Y
025 A000101 MORGAN STANLEY DEAN WITTER & CO.
025 B000101 13-2655998
025 C000101 E
025 D000101 304267
025 A000102 BEAR STEARNS & CO. INC.
025 B000102 13-3299429
025 C000102 E
025 D000102 31339
025 D000103 0
025 D000104 0
025 D000105 0
025 D000106 0
025 D000107 0
025 D000108 0
028 A010100 1960690
028 A020100 0
028 A030100 0
028 A040100 827393
028 B010100 1618430
028 B020100 0
028 B030100 0
028 B040100 1347798
028 C010100 1635932
028 C020100 154947
028 C030100 0
028 C040100 983587
028 D010100 1281154
028 D020100 0
<PAGE> PAGE 7
028 D030100 0
028 D040100 1171220
028 E010100 1644051
028 E020100 0
028 E030100 0
028 E040100 771042
028 F010100 1994292
028 F020100 487728
028 F030100 0
028 F040100 1315570
028 G010100 10134549
028 G020100 642675
028 G030100 0
028 G040100 6416610
028 H000100 0
070 A010100 Y
070 A020100 Y
070 B010100 Y
070 B020100 N
070 C010100 N
070 C020100 N
070 D010100 Y
070 D020100 N
070 E010100 N
070 E020100 N
070 F010100 Y
070 F020100 Y
070 G010100 Y
070 G020100 N
070 H010100 Y
070 H020100 N
070 I010100 N
070 I020100 N
070 J010100 Y
070 J020100 N
070 K010100 Y
070 K020100 N
070 L010100 Y
070 L020100 Y
070 M010100 N
070 M020100 N
070 N010100 Y
070 N020100 Y
070 O010100 Y
070 O020100 N
070 P010100 Y
070 P020100 Y
070 Q010100 N
070 Q020100 N
070 R010100 N
070 R020100 N
<PAGE> PAGE 8
071 A000100 14014047
071 B000100 3349516
071 C000100 60203682
071 D000100 6
072 A000100 12
072 B000100 32484
072 C000100 898388
072 D000100 0
072 E000100 995
072 F000100 80
072 G000100 45823
072 H000100 0
072 I000100 47105
072 J000100 151
072 K000100 0
072 L000100 1608
072 M000100 105
072 N000100 0
072 O000100 0
072 P000100 0
072 Q000100 0
072 R000100 45
072 S000100 0
072 T000100 15206
072 U000100 0
072 V000100 180
072 W000100 0
072 X000100 110303
072 Y000100 0
072 Z000100 821564
072AA000100 1648106
072BB000100 128895
072CC010100 13039461
072CC020100 0
072DD010100 822586
072DD020100 0
072EE000100 262081
073 A010100 1.3300
073 A020100 0.0000
073 B000100 0.4200
073 C000100 0.0000
074 A000100 38
074 B000100 469814
074 C000100 38243
074 D000100 0
074 E000100 0
074 F000100 73813849
074 G000100 0
074 H000100 0
074 I000100 12451
074 J000100 382158
<PAGE> PAGE 9
074 K000100 0
074 L000100 442451
074 M000100 0
074 N000100 75159004
074 O000100 697610
074 P000100 16854
074 Q000100 0
074 R010100 0
074 R020100 0
074 R030100 0
074 R040100 216014
074 S000100 0
074 T000100 74228526
074 U010100 651398
074 U020100 0
074 V010100 113.95
074 V020100 0.00
074 W000100 0.0000
074 X000100 1883829
074 Y000100 38243
075 A000100 0
075 B000100 60729871
076 000100 0.00
015 A000201 STATE STREET BANK AND TRUST COMPANY
015 B000201 C
015 C010201 BOSTON
015 C020201 MA
015 C030201 02110
015 E010201 X
024 000200 Y
025 A000201 PAINEWEBBER INC.
025 B000201 13-2638166
025 C000201 E
025 D000201 6528
025 A000202 INVESTMENT TECHNOLOGY GROUP, INC.
025 B000202 95-4339369
025 C000202 E
025 D000202 2116
025 A000203 DELETE
025 D000203 0
025 D000204 0
025 D000205 0
025 D000206 0
025 D000207 0
025 D000208 0
028 A010200 127791
028 A020200 0
028 A030200 0
028 A040200 122248
028 B010200 51821
028 B020200 0
<PAGE> PAGE 10
028 B030200 0
028 B040200 71695
028 C010200 55487
028 C020200 0
028 C030200 0
028 C040200 51830
028 D010200 43770
028 D020200 0
028 D030200 0
028 D040200 53431
028 E010200 71193
028 E020200 0
028 E030200 0
028 E040200 37321
028 F010200 66274
028 F020200 207116
028 F030200 0
028 F040200 105428
028 G010200 416336
028 G020200 207116
028 G030200 0
028 G040200 441953
028 H000200 0
055 A000200 N
055 B000200 N
056 000200 N
057 000200 N
066 A000200 Y
066 B000200 N
066 C000200 N
066 D000200 Y
066 E000200 N
066 F000200 N
066 G000200 N
067 000200 N
068 A000200 N
068 B000200 N
069 000200 Y
070 A010200 Y
070 A020200 Y
070 B010200 Y
070 B020200 N
070 C010200 N
070 C020200 N
070 D010200 Y
070 D020200 N
070 E010200 N
070 E020200 N
070 F010200 Y
070 F020200 Y
070 G010200 Y
<PAGE> PAGE 11
070 G020200 N
070 H010200 Y
070 H020200 N
070 I010200 N
070 I020200 N
070 J010200 Y
070 J020200 Y
070 K010200 Y
070 K020200 N
070 L010200 Y
070 L020200 Y
070 M010200 N
070 M020200 N
070 N010200 Y
070 N020200 Y
070 O010200 Y
070 O020200 N
070 P010200 Y
070 P020200 Y
070 Q010200 N
070 Q020200 N
070 R010200 N
070 R020200 N
071 A000200 923733
071 B000200 860026
071 C000200 3150696
071 D000200 27
072 A000200 12
072 B000200 4750
072 C000200 37381
072 D000200 0
072 E000200 4539
072 F000200 73
072 G000200 2265
072 H000200 0
072 I000200 3446
072 J000200 175
072 K000200 0
072 L000200 88
072 M000200 6
072 N000200 0
072 O000200 0
072 P000200 0
072 Q000200 0
072 R000200 10
072 S000200 0
072 T000200 823
072 U000200 0
072 V000200 11
072 W000200 0
072 X000200 6897
<PAGE> PAGE 12
072 Y000200 34
072 Z000200 39807
072AA000200 454075
072BB000200 86993
072CC010200 0
072CC020200 154493
072DD010200 33806
072DD020200 5556
072EE000200 225920
073 A010200 0.3730
073 A020200 0.4120
073 B000200 2.1700
073 C000200 0.0000
074 A000200 0
074 B000200 330413
074 C000200 2495
074 D000200 0
074 E000200 0
074 F000200 3316354
074 G000200 0
074 H000200 0
074 I000200 574
074 J000200 143690
074 K000200 0
074 L000200 18447
074 M000200 0
074 N000200 3811973
074 O000200 83155
074 P000200 1053
074 Q000200 0
074 R010200 0
074 R020200 0
074 R030200 0
074 R040200 332606
074 S000200 0
074 T000200 3395159
074 U010200 95929
074 U020200 14901
074 V010200 30.63
074 V020200 30.63
074 W000200 0.0000
074 X000200 106164
074 Y000200 2495
075 A000200 0
075 B000200 3238180
076 000200 0.00
015 A000301 STATE STREET BANK AND TRUST COMPANY
015 B000301 C
015 C010301 BOSTON
015 C020301 MA
015 C030301 02110
<PAGE> PAGE 13
015 E010301 X
024 000300 Y
025 A000301 MORGAN STANLEY DEAN WITTER & CO.
025 B000301 13-2655998
025 C000301 E
025 D000301 37651
025 A000302 PAINEWEBBER INCORPORATED
025 B000302 13-2638166
025 C000302 E
025 D000302 4830
025 A000303 BEAR STEARNS CO., INC.
025 B000303 13-3299429
025 C000303 E
025 D000303 3796
025 A000304 DELETE
025 D000304 0
025 D000305 0
025 D000306 0
025 D000307 0
025 D000308 0
028 A010300 402180
028 A020300 0
028 A030300 0
028 A040300 175428
028 B010300 617580
028 B020300 0
028 B030300 0
028 B040300 134525
028 C010300 435243
028 C020300 22131
028 C030300 0
028 C040300 147822
028 D010300 412903
028 D020300 0
028 D030300 0
028 D040300 144989
028 E010300 304586
028 E020300 0
028 E030300 0
028 E040300 131401
028 F010300 392936
028 F020300 90418
028 F030300 0
028 F040300 132582
028 G010300 2565428
028 G020300 112549
028 G030300 0
028 G040300 866747
028 H000300 0
070 A010300 Y
070 A020300 Y
<PAGE> PAGE 14
070 B010300 Y
070 B020300 N
070 C010300 N
070 C020300 N
070 D010300 Y
070 D020300 N
070 E010300 N
070 E020300 N
070 F010300 Y
070 F020300 Y
070 G010300 Y
070 G020300 N
070 H010300 Y
070 H020300 N
070 I010300 N
070 I020300 N
070 J010300 Y
070 J020300 Y
070 K010300 Y
070 K020300 N
070 L010300 Y
070 L020300 Y
070 M010300 N
070 M020300 N
070 N010300 Y
070 N020300 Y
070 O010300 Y
070 O020300 N
070 P010300 Y
070 P020300 Y
070 Q010300 N
070 Q020300 N
070 R010300 N
070 R020300 N
071 A000300 3535598
071 B000300 213399
071 C000300 8438357
071 D000300 3
072 A000300 12
072 B000300 23390
072 C000300 118554
072 D000300 0
072 E000300 3182
072 F000300 82
072 G000300 5836
072 H000300 0
072 I000300 7294
072 J000300 292
072 K000300 0
072 L000300 108
072 M000300 15
<PAGE> PAGE 15
072 N000300 0
072 O000300 0
072 P000300 0
072 Q000300 0
072 R000300 13
072 S000300 0
072 T000300 2200
072 U000300 0
072 V000300 17
072 W000300 0
072 X000300 15857
072 Y000300 37
072 Z000300 129306
072AA000300 165060
072BB000300 87865
072CC010300 1758376
072CC020300 0
072DD010300 100035
072DD020300 28557
072EE000300 48109
073 A010300 0.3290
073 A020300 0.3520
073 B000300 0.1250
073 C000300 0.0000
074 A000300 0
074 B000300 722165
074 C000300 21979
074 D000300 0
074 E000300 0
074 F000300 11210503
074 G000300 0
074 H000300 0
074 I000300 1925
074 J000300 44915
074 K000300 0
074 L000300 41000
074 M000300 0
074 N000300 12042487
074 O000300 1572
074 P000300 2227
074 Q000300 0
074 R010300 0
074 R020300 0
074 R030300 0
074 R040300 285569
074 S000300 0
074 T000300 11753119
074 U010300 339456
074 U020300 89179
074 V010300 27.42
074 V020300 27.42
<PAGE> PAGE 16
074 W000300 0.0000
074 X000300 224355
074 Y000300 21979
075 A000300 0
075 B000300 8849541
076 000300 0.00
015 A000401 FIRST UNION NATIONAL BANK
015 B000401 C
015 C010401 PHILADELPHIA
015 C020401 PA
015 C030401 19101
015 E010401 X
024 000400 Y
025 A000401 MORGAN STANLEY DEAN WITTER & CO.
025 B000401 13-2655998
025 C000401 E
025 D000401 23267
025 A000402 BEAR STEARNS & CO., INC.
025 B000402 13-3299429
025 C000402 E
025 D000402 2426
025 D000403 0
025 D000404 0
025 D000405 0
025 D000406 0
025 D000407 0
025 D000408 0
028 A010400 101740
028 A020400 0
028 A030400 0
028 A040400 50801
028 B010400 75711
028 B020400 0
028 B030400 0
028 B040400 53170
028 C010400 52449
028 C020400 6441
028 C030400 0
028 C040400 40225
028 D010400 172545
028 D020400 2
028 D030400 0
028 D040400 72509
028 E010400 60190
028 E020400 0
028 E030400 0
028 E040400 44264
028 F010400 104904
028 F020400 77844
028 F030400 0
028 F040400 49475
<PAGE> PAGE 17
028 G010400 567539
028 G020400 84287
028 G030400 0
028 G040400 310444
028 H000400 0
066 A000400 Y
066 B000400 N
066 C000400 N
066 D000400 N
066 E000400 Y
066 F000400 N
066 G000400 N
067 000400 N
068 A000400 N
068 B000400 N
069 000400 Y
070 A010400 Y
070 A020400 Y
070 B010400 Y
070 B020400 N
070 C010400 N
070 C020400 N
070 D010400 Y
070 D020400 N
070 E010400 N
070 E020400 N
070 F010400 Y
070 F020400 Y
070 G010400 Y
070 G020400 N
070 H010400 Y
070 H020400 N
070 I010400 N
070 I020400 N
070 J010400 Y
070 J020400 N
070 K010400 Y
070 K020400 N
070 L010400 Y
070 L020400 Y
070 M010400 N
070 M020400 N
070 N010400 Y
070 N020400 Y
070 O010400 Y
070 O020400 N
070 P010400 Y
070 P020400 Y
070 Q010400 N
070 Q020400 N
070 R010400 N
<PAGE> PAGE 18
070 R020400 N
071 A000400 1277847
071 B000400 706182
071 C000400 2163522
071 D000400 33
072 A000400 12
072 B000400 398
072 C000400 41768
072 D000400 0
072 E000400 54
072 F000400 37
072 G000400 1617
072 H000400 0
072 I000400 2365
072 J000400 76
072 K000400 0
072 L000400 66
072 M000400 4
072 N000400 0
072 O000400 0
072 P000400 0
072 Q000400 0
072 R000400 9
072 S000400 0
072 T000400 580
072 U000400 0
072 V000400 9
072 W000400 0
072 X000400 4763
072 Y000400 0
072 Z000400 37457
072AA000400 170714
072BB000400 22675
072CC010400 110054
072CC020400 0
072DD010400 36542
072DD020400 1280
072EE000400 102718
073 A010400 0.3630
073 A020400 0.2360
073 B000400 0.9900
073 C000400 0.0000
074 A000400 1
074 B000400 7133
074 C000400 399
074 D000400 0
074 E000400 0
074 F000400 2614671
074 G000400 0
074 H000400 0
074 I000400 441
<PAGE> PAGE 19
074 J000400 345827
074 K000400 0
074 L000400 10035
074 M000400 0
074 N000400 2978507
074 O000400 359770
074 P000400 611
074 Q000400 0
074 R010400 0
074 R020400 0
074 R030400 0
074 R040400 11413
074 S000400 0
074 T000400 2606713
074 U010400 107548
074 U020400 8269
074 V010400 22.51
074 V020400 22.51
074 W000400 0.0000
074 X000400 90420
074 Y000400 399
075 A000400 0
075 B000400 2179253
076 000400 0.00
015 A000501 FIRST UNION NATIONAL BANK
015 B000501 C
015 C010501 PHILADELPHIA
015 C020501 PA
015 C030501 19101
015 E010501 X
024 000500 N
025 A000501 MORGAN STANLEY, DEAN WITTER, DISCOVER & CO.
025 B000501 13-2655998
025 C000501 E
025 D000501 21403
028 A010500 387586
028 A020500 0
028 A030500 0
028 A040500 62750
028 B010500 347141
028 B020500 0
028 B030500 0
028 B040500 139284
028 C010500 281326
028 C020500 7987
028 C030500 0
028 C040500 93047
028 D010500 446331
028 D020500 0
028 D030500 0
028 D040500 241762
<PAGE> PAGE 20
028 E010500 511631
028 E020500 0
028 E030500 0
028 E040500 70902
028 F010500 590598
028 F020500 35842
028 F030500 0
028 F040500 118216
028 G010500 2564613
028 G020500 43829
028 G030500 0
028 G040500 725961
028 H000500 0
070 A010500 Y
070 A020500 Y
070 B010500 Y
070 B020500 N
070 C010500 N
070 C020500 N
070 D010500 Y
070 D020500 N
070 E010500 N
070 E020500 N
070 F010500 Y
070 F020500 Y
070 G010500 Y
070 G020500 N
070 H010500 Y
070 H020500 N
070 I010500 N
070 I020500 N
070 J010500 Y
070 J020500 N
070 K010500 Y
070 K020500 N
070 L010500 Y
070 L020500 Y
070 M010500 N
070 M020500 N
070 N010500 Y
070 N020500 Y
070 O010500 Y
070 O020500 N
070 P010500 Y
070 P020500 Y
070 Q010500 N
070 Q020500 N
070 R010500 N
070 R020500 N
071 A000500 4222787
071 B000500 1192518
<PAGE> PAGE 21
071 C000500 4127558
071 D000500 29
072 A000500 12
072 B000500 1732
072 C000500 45207
072 D000500 0
072 E000500 14
072 F000500 37
072 G000500 3216
072 H000500 0
072 I000500 4499
072 J000500 34
072 K000500 0
072 L000500 105
072 M000500 7
072 N000500 0
072 O000500 0
072 P000500 0
072 Q000500 0
072 R000500 10
072 S000500 0
072 T000500 1070
072 U000500 0
072 V000500 15
072 W000500 0
072 X000500 8993
072 Y000500 0
072 Z000500 37960
072AA000500 152424
072BB000500 79538
072CC010500 1404145
072CC020500 0
072DD010500 36372
072DD020500 693
072EE000500 23968
073 A010500 0.2190
073 A020500 0.1870
073 B000500 0.1150
073 C000500 0.0000
074 A000500 1
074 B000500 42743
074 C000500 599
074 D000500 0
074 E000500 0
074 F000500 6854976
074 G000500 0
074 H000500 0
074 I000500 1057
074 J000500 777496
074 K000500 0
074 L000500 58326
<PAGE> PAGE 22
074 M000500 0
074 N000500 7735198
074 O000500 856779
074 P000500 965
074 Q000500 0
074 R010500 0
074 R020500 0
074 R030500 0
074 R040500 8954
074 S000500 0
074 T000500 6868500
074 U010500 209802
074 U020500 7079
074 V010500 31.67
074 V020500 31.67
074 W000500 0.0000
074 X000500 238094
074 Y000500 599
075 A000500 0
075 B000500 4125027
076 000500 0.00
015 A000601 FIRST UNION NATIONAL BANK
015 B000601 C
015 C010601 PHILADELPHIA
015 C020601 PA
015 C030601 19101
015 E010601 X
024 000600 Y
025 A000601 INVESTMENT TECHNOLOGY GROUP, INC.
025 B000601 95-4339369
025 C000601 E
025 D000601 1992
025 D000602 0
025 D000603 0
025 D000604 0
025 D000605 0
025 D000606 0
025 D000607 0
025 D000608 0
028 A010600 86377
028 A020600 0
028 A030600 0
028 A040600 107164
028 B010600 69293
028 B020600 0
028 B030600 0
028 B040600 76432
028 C010600 76281
028 C020600 0
028 C030600 0
028 C040600 37789
<PAGE> PAGE 23
028 D010600 106357
028 D020600 0
028 D030600 0
028 D040600 58194
028 E010600 93406
028 E020600 0
028 E030600 0
028 E040600 42999
028 F010600 146746
028 F020600 200711
028 F030600 0
028 F040600 120114
028 G010600 578460
028 G020600 200711
028 G030600 0
028 G040600 442692
028 H000600 0
055 A000600 N
055 B000600 N
056 000600 N
057 000600 N
066 A000600 Y
066 B000600 N
066 C000600 Y
066 D000600 N
066 E000600 N
066 F000600 N
066 G000600 N
067 000600 N
068 A000600 N
068 B000600 N
069 000600 Y
070 A010600 Y
070 A020600 Y
070 B010600 Y
070 B020600 N
070 C010600 N
070 C020600 N
070 D010600 Y
070 D020600 N
070 E010600 N
070 E020600 N
070 F010600 Y
070 F020600 Y
070 G010600 Y
070 G020600 N
070 H010600 Y
070 H020600 N
070 I010600 N
070 I020600 N
070 J010600 Y
<PAGE> PAGE 24
070 J020600 Y
070 K010600 Y
070 K020600 N
070 L010600 Y
070 L020600 Y
070 M010600 N
070 M020600 N
070 N010600 Y
070 N020600 Y
070 O010600 Y
070 O020600 N
070 P010600 Y
070 P020600 Y
070 Q010600 N
070 Q020600 N
070 R010600 N
070 R020600 N
071 A000600 1298866
071 B000600 961558
071 C000600 2785729
071 D000600 35
072 A000600 12
072 B000600 5515
072 C000600 38503
072 D000600 0
072 E000600 2866
072 F000600 100
072 G000600 2399
072 H000600 0
072 I000600 3168
072 J000600 86
072 K000600 0
072 L000600 102
072 M000600 6
072 N000600 0
072 O000600 0
072 P000600 0
072 Q000600 0
072 R000600 10
072 S000600 0
072 T000600 802
072 U000600 0
072 V000600 13
072 W000600 0
072 X000600 6686
072 Y000600 4
072 Z000600 40202
072AA000600 333720
072BB000600 134176
072CC010600 0
072CC020600 318857
<PAGE> PAGE 25
072DD010600 37309
072DD020600 3153
072EE000600 203417
073 A010600 0.3040
073 A020600 0.3290
073 B000600 1.5500
073 C000600 0.0000
074 A000600 54
074 B000600 292926
074 C000600 5896
074 D000600 0
074 E000600 0
074 F000600 2929234
074 G000600 0
074 H000600 0
074 I000600 504
074 J000600 4956
074 K000600 0
074 L000600 28161
074 M000600 0
074 N000600 3261731
074 O000600 20743
074 P000600 946
074 Q000600 0
074 R010600 0
074 R020600 0
074 R030600 0
074 R040600 207686
074 S000600 0
074 T000600 3032356
074 U010600 130588
074 U020600 12467
074 V010600 21.20
074 V020600 21.20
074 W000600 0.0000
074 X000600 116140
074 Y000600 5896
075 A000600 0
075 B000600 2884406
076 000600 0.00
015 A000701 FIRST UNION NATIONAL BANK
015 B000701 C
015 C010701 PHILADELPHIA
015 C020701 PA
015 C030701 19101
015 E010701 X
024 000700 N
028 A010700 37750
028 A020700 0
028 A030700 0
028 A040700 1811
<PAGE> PAGE 26
028 B010700 19015
028 B020700 0
028 B030700 0
028 B040700 4077
028 C010700 13452
028 C020700 0
028 C030700 0
028 C040700 2915
028 D010700 10624
028 D020700 0
028 D030700 0
028 D040700 3038
028 E010700 15282
028 E020700 0
028 E030700 0
028 E040700 2832
028 F010700 21941
028 F020700 1867
028 F030700 0
028 F040700 3008
028 G010700 118064
028 G020700 1867
028 G030700 0
028 G040700 17681
028 H000700 0
055 A000700 Y
055 B000700 N
056 000700 N
057 000700 N
066 A000700 Y
066 B000700 N
066 C000700 N
066 D000700 Y
066 E000700 N
066 F000700 N
066 G000700 N
067 000700 N
068 A000700 N
068 B000700 N
069 000700 Y
070 A010700 Y
070 A020700 Y
070 B010700 Y
070 B020700 N
070 C010700 N
070 C020700 N
070 D010700 Y
070 D020700 N
070 E010700 N
070 E020700 N
070 F010700 Y
<PAGE> PAGE 27
070 F020700 Y
070 G010700 Y
070 G020700 N
070 H010700 Y
070 H020700 N
070 I010700 N
070 I020700 N
070 J010700 Y
070 J020700 N
070 K010700 Y
070 K020700 N
070 L010700 Y
070 L020700 Y
070 M010700 N
070 M020700 N
070 N010700 Y
070 N020700 Y
070 O010700 Y
070 O020700 N
070 P010700 Y
070 P020700 Y
070 Q010700 N
070 Q020700 N
070 R010700 N
070 R020700 N
071 A000700 275842
071 B000700 64873
071 C000700 148824
071 D000700 44
072 A000700 12
072 B000700 165
072 C000700 1184
072 D000700 0
072 E000700 9
072 F000700 20
072 G000700 44
072 H000700 0
072 I000700 120
072 J000700 21
072 K000700 0
072 L000700 0
072 M000700 0
072 N000700 0
072 O000700 0
072 P000700 0
072 Q000700 0
072 R000700 0
072 S000700 0
072 T000700 10
072 U000700 0
072 V000700 0
<PAGE> PAGE 28
072 W000700 0
072 X000700 215
072 Y000700 0
072 Z000700 1143
072AA000700 17931
072BB000700 2086
072CC010700 9050
072CC020700 0
072DD010700 962
072DD020700 210
072EE000700 1085
073 A010700 0.0530
073 A020700 0.0590
073 B000700 0.0500
073 C000700 0.0000
074 A000700 0
074 B000700 6263
074 C000700 200
074 D000700 0
074 E000700 0
074 F000700 235228
074 G000700 0
074 H000700 0
074 I000700 42
074 J000700 27072
074 K000700 0
074 L000700 6786
074 M000700 0
074 N000700 275591
074 O000700 30190
074 P000700 20
074 Q000700 0
074 R010700 0
074 R020700 0
074 R030700 0
074 R040700 1036
074 S000700 0
074 T000700 244345
074 U010700 19066
074 U020700 3586
074 V010700 10.79
074 V020700 10.79
074 W000700 0.0000
074 X000700 9537
074 Y000700 200
075 A000700 0
075 B000700 135877
076 000700 0.00
015 A000801 FIRST UNION NATIONAL BANK
015 B000801 C
015 C010801 PHILADELPHIA
<PAGE> PAGE 29
015 C020801 PA
015 C030801 19101
015 E010801 X
024 000800 N
028 A010800 6922
028 A020800 0
028 A030800 0
028 A040800 2072
028 B010800 8816
028 B020800 0
028 B030800 0
028 B040800 3219
028 C010800 8291
028 C020800 0
028 C030800 0
028 C040800 3390
028 D010800 8191
028 D020800 0
028 D030800 0
028 D040800 2830
028 E010800 8620
028 E020800 0
028 E030800 0
028 E040800 2424
028 F010800 8198
028 F020800 627
028 F030800 0
028 F040800 5665
028 G010800 49038
028 G020800 627
028 G030800 0
028 G040800 19600
028 H000800 0
055 A000800 N
055 B000800 N
056 000800 N
057 000800 N
066 A000800 Y
066 B000800 N
066 C000800 Y
066 D000800 N
066 E000800 N
066 F000800 N
066 G000800 N
067 000800 N
068 A000800 N
068 B000800 N
069 000800 Y
070 A010800 Y
070 A020800 Y
070 B010800 Y
<PAGE> PAGE 30
070 B020800 N
070 C010800 N
070 C020800 N
070 D010800 Y
070 D020800 N
070 E010800 N
070 E020800 N
070 F010800 Y
070 F020800 Y
070 G010800 Y
070 G020800 N
070 H010800 Y
070 H020800 N
070 I010800 N
070 I020800 N
070 J010800 Y
070 J020800 N
070 K010800 Y
070 K020800 N
070 L010800 Y
070 L020800 Y
070 M010800 N
070 M020800 N
070 N010800 Y
070 N020800 Y
070 O010800 Y
070 O020800 N
070 P010800 Y
070 P020800 Y
070 Q010800 N
070 Q020800 N
070 R010800 N
070 R020800 N
071 A000800 175041
071 B000800 46669
071 C000800 87684
071 D000800 53
072 A000800 12
072 B000800 103
072 C000800 642
072 D000800 0
072 E000800 33
072 F000800 20
072 G000800 13
072 H000800 0
072 I000800 84
072 J000800 17
072 K000800 0
072 L000800 0
072 M000800 0
072 N000800 0
<PAGE> PAGE 31
072 O000800 0
072 P000800 0
072 Q000800 0
072 R000800 0
072 S000800 0
072 T000800 5
072 U000800 0
072 V000800 0
072 W000800 0
072 X000800 139
072 Y000800 0
072 Z000800 639
072AA000800 3308
072BB000800 2826
072CC010800 0
072CC020800 11368
072DD010800 705
072DD020800 0
072EE000800 0
073 A010800 0.0550
073 A020800 0.0000
073 B000800 0.0000
073 C000800 0.0000
074 A000800 0
074 B000800 2531
074 C000800 100
074 D000800 0
074 E000800 0
074 F000800 117282
074 G000800 0
074 H000800 0
074 I000800 21
074 J000800 14524
074 K000800 0
074 L000800 697
074 M000800 0
074 N000800 135155
074 O000800 19053
074 P000800 13
074 Q000800 0
074 R010800 0
074 R020800 0
074 R030800 0
074 R040800 3524
074 S000800 0
074 T000800 112565
074 U010800 12885
074 U020800 0
074 V010800 8.74
074 V020800 0.00
074 W000800 0.0000
<PAGE> PAGE 32
074 X000800 7031
074 Y000800 0
075 A000800 0
075 B000800 80848
076 000800 0.00
015 A000901 FIRST UNION NATIONAL BANK
015 B000901 C
015 C010901 PHILADELPHIA
015 C020901 PA
015 C030901 19101
015 E010901 X
024 000900 N
028 A010900 4938
028 A020900 0
028 A030900 0
028 A040900 1310
028 B010900 3578
028 B020900 0
028 B030900 0
028 B040900 2291
028 C010900 4332
028 C020900 0
028 C030900 0
028 C040900 1386
028 D010900 7741
028 D020900 0
028 D030900 0
028 D040900 1611
028 E010900 8223
028 E020900 0
028 E030900 0
028 E040900 1880
028 F010900 6964
028 F020900 232
028 F030900 0
028 F040900 2428
028 G010900 35776
028 G020900 232
028 G030900 0
028 G040900 10906
028 H000900 0
055 A000900 Y
055 B000900 N
056 000900 N
057 000900 N
066 A000900 Y
066 B000900 N
066 C000900 Y
066 D000900 N
066 E000900 N
066 F000900 N
<PAGE> PAGE 33
066 G000900 N
067 000900 N
068 A000900 N
068 B000900 N
069 000900 Y
070 A010900 Y
070 A020900 Y
070 B010900 Y
070 B020900 N
070 C010900 N
070 C020900 N
070 D010900 Y
070 D020900 N
070 E010900 N
070 E020900 N
070 F010900 Y
070 F020900 Y
070 G010900 Y
070 G020900 N
070 H010900 Y
070 H020900 N
070 I010900 N
070 I020900 N
070 J010900 Y
070 J020900 N
070 K010900 Y
070 K020900 N
070 L010900 Y
070 L020900 Y
070 M010900 N
070 M020900 N
070 N010900 Y
070 N020900 Y
070 O010900 Y
070 O020900 N
070 P010900 Y
070 P020900 Y
070 Q010900 N
070 Q020900 N
070 R010900 N
070 R020900 N
071 A000900 134005
071 B000900 45145
071 C000900 58931
071 D000900 77
072 A000900 12
072 B000900 88
072 C000900 226
072 D000900 0
072 E000900 38
072 F000900 20
<PAGE> PAGE 34
072 G000900 1
072 H000900 0
072 I000900 60
072 J000900 14
072 K000900 0
072 L000900 0
072 M000900 0
072 N000900 0
072 O000900 0
072 P000900 0
072 Q000900 0
072 R000900 0
072 S000900 0
072 T000900 4
072 U000900 0
072 V000900 0
072 W000900 0
072 X000900 99
072 Y000900 0
072 Z000900 253
072AA000900 1431
072BB000900 6998
072CC010900 5558
072CC020900 0
072DD010900 281
072DD020900 0
072EE000900 0
073 A010900 0.0300
073 A020900 0.0000
073 B000900 0.0000
073 C000900 0.0000
074 A000900 0
074 B000900 2669
074 C000900 0
074 D000900 0
074 E000900 0
074 F000900 88655
074 G000900 0
074 H000900 0
074 I000900 14
074 J000900 11817
074 K000900 0
074 L000900 801
074 M000900 0
074 N000900 103956
074 O000900 11177
074 P000900 10
074 Q000900 0
074 R010900 0
074 R020900 0
074 R030900 0
<PAGE> PAGE 35
074 R040900 2651
074 S000900 0
074 T000900 90118
074 U010900 9451
074 U020900 0
074 V010900 9.53
074 V020900 0.00
074 W000900 0.0000
074 X000900 6327
074 Y000900 0
075 A000900 0
075 B000900 57505
076 000900 0.00
SIGNATURE GARY P. SOURA
TITLE MANAGER
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 01
<NAME> VANGUARD 500 INDEX FUND
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 43332020
<INVESTMENTS-AT-VALUE> 74321906
<RECEIVABLES> 824609
<ASSETS-OTHER> 12489
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 75159004
<PAYABLE-FOR-SECURITIES> 697610
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 232868
<TOTAL-LIABILITIES> 930478
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 42935110
<SHARES-COMMON-STOCK> 651398
<SHARES-COMMON-PRIOR> 547990
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 6151
<ACCUMULATED-NET-GAINS> 296685
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 31002882
<NET-ASSETS> 74228526
<DIVIDEND-INCOME> 898388
<INTEREST-INCOME> 32484
<OTHER-INCOME> 995
<EXPENSES-NET> 110303
<NET-INVESTMENT-INCOME> 821564
<REALIZED-GAINS-CURRENT> 1519211
<APPREC-INCREASE-CURRENT> 13039461
<NET-CHANGE-FROM-OPS> 15380236
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 822586
<DISTRIBUTIONS-OF-GAINS> 262081
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 205796
<NUMBER-OF-SHARES-REDEEMED> 111820
<SHARES-REINVESTED> 9433
<NET-CHANGE-IN-ASSETS> 24870903
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 44740
<OVERDISTRIB-NII-PRIOR> 5129
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 80
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 110303
<AVERAGE-NET-ASSETS> 60729871
<PER-SHARE-NAV-BEGIN> 90.07
<PER-SHARE-NII> 1.33
<PER-SHARE-GAIN-APPREC> 24.30
<PER-SHARE-DIVIDEND> 1.33
<PER-SHARE-DISTRIBUTIONS> 0.42
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 113.95
<EXPENSE-RATIO> 0.18
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 021
<NAME> VANGUARD EXTENDED MARKET INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2891395
<INVESTMENTS-AT-VALUE> 3649262
<RECEIVABLES> 162137
<ASSETS-OTHER> 574
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 3811973
<PAYABLE-FOR-SECURITIES> 83155
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 333659
<TOTAL-LIABILITIES> 416814
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 2458296
<SHARES-COMMON-STOCK> 95929
<SHARES-COMMON-PRIOR> 88529
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 133
<ACCUMULATED-NET-GAINS> 176135
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 760861
<NET-ASSETS> 2938675
<DIVIDEND-INCOME> 37381
<INTEREST-INCOME> 4750
<OTHER-INCOME> 4539
<EXPENSES-NET> 6863
<NET-INVESTMENT-INCOME> 39807
<REALIZED-GAINS-CURRENT> 367082
<APPREC-INCREASE-CURRENT> (154493)
<NET-CHANGE-FROM-OPS> 252396
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 33806
<DISTRIBUTIONS-OF-GAINS> 195606
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 21213
<NUMBER-OF-SHARES-REDEEMED> 21009
<SHARES-REINVESTED> 7196
<NET-CHANGE-IN-ASSETS> 257680
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 34973
<OVERDISTRIB-NII-PRIOR> 578
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 73
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 6897
<AVERAGE-NET-ASSETS> 2782988
<PER-SHARE-NAV-BEGIN> 30.76
<PER-SHARE-NII> 0.388
<PER-SHARE-GAIN-APPREC> 2.025
<PER-SHARE-DIVIDEND> 0.373
<PER-SHARE-DISTRIBUTIONS> 2.170
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 30.63
<EXPENSE-RATIO> 0.23
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 022
<NAME> VANGUARD EXTENDED MARKET INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2891395
<INVESTMENTS-AT-VALUE> 3649262
<RECEIVABLES> 162137
<ASSETS-OTHER> 574
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 3811973
<PAYABLE-FOR-SECURITIES> 83155
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 333659
<TOTAL-LIABILITIES> 416814
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 2458296
<SHARES-COMMON-STOCK> 14901
<SHARES-COMMON-PRIOR> 13482
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 133
<ACCUMULATED-NET-GAINS> 176135
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 760861
<NET-ASSETS> 456484
<DIVIDEND-INCOME> 37381
<INTEREST-INCOME> 4750
<OTHER-INCOME> 4539
<EXPENSES-NET> 6863
<NET-INVESTMENT-INCOME> 39807
<REALIZED-GAINS-CURRENT> 367082
<APPREC-INCREASE-CURRENT> (154493)
<NET-CHANGE-FROM-OPS> 252396
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 5556
<DISTRIBUTIONS-OF-GAINS> 30314
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 7627
<NUMBER-OF-SHARES-REDEEMED> 7244
<SHARES-REINVESTED> 1037
<NET-CHANGE-IN-ASSETS> 257680
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 34973
<OVERDISTRIB-NII-PRIOR> 578
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 73
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 6897
<AVERAGE-NET-ASSETS> 455192
<PER-SHARE-NAV-BEGIN> 30.76
<PER-SHARE-NII> 0.427
<PER-SHARE-GAIN-APPREC> 2.025
<PER-SHARE-DIVIDEND> 0.412
<PER-SHARE-DISTRIBUTIONS> 2.170
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 30.63
<EXPENSE-RATIO> 0.10
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 031
<NAME> VANGUARD TOTAL STOCK MARKET INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 8365070
<INVESTMENTS-AT-VALUE> 11954647
<RECEIVABLES> 85915
<ASSETS-OTHER> 1925
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 12042487
<PAYABLE-FOR-SECURITIES> 1572
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 287796
<TOTAL-LIABILITIES> 289368
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 8092915
<SHARES-COMMON-STOCK> 339456
<SHARES-COMMON-PRIOR> 224899
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 242
<ACCUMULATED-NET-GAINS> 41321
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 3619125
<NET-ASSETS> 9307762
<DIVIDEND-INCOME> 118554
<INTEREST-INCOME> 23390
<OTHER-INCOME> 3182
<EXPENSES-NET> 15820
<NET-INVESTMENT-INCOME> 129306
<REALIZED-GAINS-CURRENT> 77195
<APPREC-INCREASE-CURRENT> 1758376
<NET-CHANGE-FROM-OPS> 1964877
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 100035
<DISTRIBUTIONS-OF-GAINS> 38015
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 160242
<NUMBER-OF-SHARES-REDEEMED> 50676
<SHARES-REINVESTED> 4991
<NET-CHANGE-IN-ASSETS> 5156662
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 12235
<OVERDISTRIB-NII-PRIOR> 956
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 82
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 15857
<AVERAGE-NET-ASSETS> 6942466
<PER-SHARE-NAV-BEGIN> 22.64
<PER-SHARE-NII> 0.336
<PER-SHARE-GAIN-APPREC> 4.898
<PER-SHARE-DIVIDEND> 0.329
<PER-SHARE-DISTRIBUTIONS> 0.125
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 27.42
<EXPENSE-RATIO> 0.20
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 032
<NAME> VANGUARD STOCK MARKET INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 8365070
<INVESTMENTS-AT-VALUE> 11954647
<RECEIVABLES> 85915
<ASSETS-OTHER> 1925
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 12042487
<PAYABLE-FOR-SECURITIES> 1572
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 287796
<TOTAL-LIABILITIES> 289368
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 8092915
<SHARES-COMMON-STOCK> 89179
<SHARES-COMMON-PRIOR> 66413
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 242
<ACCUMULATED-NET-GAINS> 41321
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 3619125
<NET-ASSETS> 2445357
<DIVIDEND-INCOME> 118554
<INTEREST-INCOME> 23390
<OTHER-INCOME> 3182
<EXPENSES-NET> 15820
<NET-INVESTMENT-INCOME> 129306
<REALIZED-GAINS-CURRENT> 77195
<APPREC-INCREASE-CURRENT> 1758376
<NET-CHANGE-FROM-OPS> 1964877
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 28557
<DISTRIBUTIONS-OF-GAINS> 10094
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 33554
<NUMBER-OF-SHARES-REDEEMED> 12173
<SHARES-REINVESTED> 1385
<NET-CHANGE-IN-ASSETS> 5156662
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 12235
<OVERDISTRIB-NII-PRIOR> 956
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 82
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 15857
<AVERAGE-NET-ASSETS> 1907075
<PER-SHARE-NAV-BEGIN> 22.64
<PER-SHARE-NII> 0.359
<PER-SHARE-GAIN-APPREC> 4.898
<PER-SHARE-DIVIDEND> 0.352
<PER-SHARE-DISTRIBUTIONS> 0.125
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 27.42
<EXPENSE-RATIO> 0.10
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 041
<NAME> VANGUARD VALUE INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2077416
<INVESTMENTS-AT-VALUE> 2622203
<RECEIVABLES> 355862
<ASSETS-OTHER> 442
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 2978507
<PAYABLE-FOR-SECURITIES> 359770
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12024
<TOTAL-LIABILITIES> 371794
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1982252
<SHARES-COMMON-STOCK> 107548
<SHARES-COMMON-PRIOR> 86130
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 551
<ACCUMULATED-NET-GAINS> 80108
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 544904
<NET-ASSETS> 2420609
<DIVIDEND-INCOME> 41768
<INTEREST-INCOME> 398
<OTHER-INCOME> 54
<EXPENSES-NET> 4763
<NET-INVESTMENT-INCOME> 37457
<REALIZED-GAINS-CURRENT> 148039
<APPREC-INCREASE-CURRENT> 110054
<NET-CHANGE-FROM-OPS> 295550
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 36542
<DISTRIBUTIONS-OF-GAINS> 98153
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 39652
<NUMBER-OF-SHARES-REDEEMED> 23806
<SHARES-REINVESTED> 5572
<NET-CHANGE-IN-ASSETS> 811172
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 34787
<OVERDISTRIB-NII-PRIOR> 186
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 37
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 4763
<AVERAGE-NET-ASSETS> 2149394
<PER-SHARE-NAV-BEGIN> 20.85
<PER-SHARE-NII> 0.366
<PER-SHARE-GAIN-APPREC> 2.647
<PER-SHARE-DIVIDEND> 0.363
<PER-SHARE-DISTRIBUTIONS> 0.990
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 22.51
<EXPENSE-RATIO> 0.22
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 042
<NAME> VANGUARD VALUE INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JUL-02-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2077416
<INVESTMENTS-AT-VALUE> 2622203
<RECEIVABLES> 355862
<ASSETS-OTHER> 442
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 2978507
<PAYABLE-FOR-SECURITIES> 359770
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 12024
<TOTAL-LIABILITIES> 371794
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1982252
<SHARES-COMMON-STOCK> 8269
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 551
<ACCUMULATED-NET-GAINS> 80108
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 544904
<NET-ASSETS> 186104
<DIVIDEND-INCOME> 41768
<INTEREST-INCOME> 398
<OTHER-INCOME> 54
<EXPENSES-NET> 4763
<NET-INVESTMENT-INCOME> 37457
<REALIZED-GAINS-CURRENT> 148039
<APPREC-INCREASE-CURRENT> 110054
<NET-CHANGE-FROM-OPS> 295550
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 1280
<DISTRIBUTIONS-OF-GAINS> 4565
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 8040
<NUMBER-OF-SHARES-REDEEMED> 3
<SHARES-REINVESTED> 232
<NET-CHANGE-IN-ASSETS> 811172
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 34787
<OVERDISTRIB-NII-PRIOR> 186
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 37
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 4763
<AVERAGE-NET-ASSETS> 60885
<PER-SHARE-NAV-BEGIN> 23.22
<PER-SHARE-NII> 0.196
<PER-SHARE-GAIN-APPREC> (0.06)
<PER-SHARE-DIVIDEND> 0.236
<PER-SHARE-DISTRIBUTIONS> 0.61
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 22.51
<EXPENSE-RATIO> 0.12
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 051
<NAME> VANGUARD GROWTH INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 4947187
<INVESTMENTS-AT-VALUE> 6898318
<RECEIVABLES> 835822
<ASSETS-OTHER> 1058
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 7735198
<PAYABLE-FOR-SECURITIES> 856779
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 9919
<TOTAL-LIABILITIES> 866698
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4877998
<SHARES-COMMON-STOCK> 209802
<SHARES-COMMON-PRIOR> 104984
<ACCUMULATED-NII-CURRENT> 374
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 38663
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 1951465
<NET-ASSETS> 6644305
<DIVIDEND-INCOME> 45207
<INTEREST-INCOME> 1732
<OTHER-INCOME> 14
<EXPENSES-NET> 8993
<NET-INVESTMENT-INCOME> 37960
<REALIZED-GAINS-CURRENT> 72886
<APPREC-INCREASE-CURRENT> 1404145
<NET-CHANGE-FROM-OPS> 1514991
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 36372
<DISTRIBUTIONS-OF-GAINS> 23155
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 140735
<NUMBER-OF-SHARES-REDEEMED> 37803
<SHARES-REINVESTED> 1885
<NET-CHANGE-IN-ASSETS> 4503167
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 521
<OVERDIST-NET-GAINS-PRIOR> 8937
<GROSS-ADVISORY-FEES> 37
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 8993
<AVERAGE-NET-ASSETS> 4065327
<PER-SHARE-NAV-BEGIN> 22.53
<PER-SHARE-NII> 0.230
<PER-SHARE-GAIN-APPREC> 9.244
<PER-SHARE-DIVIDEND> 0.219
<PER-SHARE-DISTRIBUTIONS> 0.115
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 31.67
<EXPENSE-RATIO> 0.22
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<RESTATED>
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 052
<NAME> VANGUARD GROWTH INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1,000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> MAY-14-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 4947187
<INVESTMENTS-AT-VALUE> 6898318
<RECEIVABLES> 835822
<ASSETS-OTHER> 1058
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 7735198
<PAYABLE-FOR-SECURITIES> 856779
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 9919
<TOTAL-LIABILITIES> 866698
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4877998
<SHARES-COMMON-STOCK> 7079
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 374
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 38663
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 1951465
<NET-ASSETS> 224195
<DIVIDEND-INCOME> 45207
<INTEREST-INCOME> 1732
<OTHER-INCOME> 14
<EXPENSES-NET> 8993
<NET-INVESTMENT-INCOME> 37960
<REALIZED-GAINS-CURRENT> 72886
<APPREC-INCREASE-CURRENT> 1404145
<NET-CHANGE-FROM-OPS> 1514991
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 693
<DISTRIBUTIONS-OF-GAINS> 813
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 7955
<NUMBER-OF-SHARES-REDEEMED> 925
<SHARES-REINVESTED> 49
<NET-CHANGE-IN-ASSETS> 4503167
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 521
<OVERDIST-NET-GAINS-PRIOR> 8937
<GROSS-ADVISORY-FEES> 37
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 8993
<AVERAGE-NET-ASSETS> 94331
<PER-SHARE-NAV-BEGIN> 26.49
<PER-SHARE-NII> 0.167
<PER-SHARE-GAIN-APPREC> 5.315
<PER-SHARE-DIVIDEND> 0.187
<PER-SHARE-DISTRIBUTIONS> 0.115
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 31.67
<EXPENSE-RATIO> 0.12
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 061
<NAME> VANGUARD SMALL-CAP INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2986293
<INVESTMENTS-AT-VALUE> 3228056
<RECEIVABLES> 33117
<ASSETS-OTHER> 558
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 3261731
<PAYABLE-FOR-SECURITIES> 20743
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 208632
<TOTAL-LIABILITIES> 229375
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 2769161
<SHARES-COMMON-STOCK> 130588
<SHARES-COMMON-PRIOR> 111668
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 641
<ACCUMULATED-NET-GAINS> 14857
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 248979
<NET-ASSETS> 2768079
<DIVIDEND-INCOME> 38503
<INTEREST-INCOME> 5515
<OTHER-INCOME> 2866
<EXPENSES-NET> 6682
<NET-INVESTMENT-INCOME> 40202
<REALIZED-GAINS-CURRENT> 199544
<APPREC-INCREASE-CURRENT> (318857)
<NET-CHANGE-FROM-OPS> (79111)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 37309
<DISTRIBUTIONS-OF-GAINS> 188747
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 42704
<NUMBER-OF-SHARES-REDEEMED> 33911
<SHARES-REINVESTED> 10127
<NET-CHANGE-IN-ASSETS> 243062
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 18730
<OVERDISTRIB-NII-PRIOR> 381
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 100
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 6686
<AVERAGE-NET-ASSETS> 2686647
<PER-SHARE-NAV-BEGIN> 23.75
<PER-SHARE-NII> 0.311
<PER-SHARE-GAIN-APPREC> (1.007)
<PER-SHARE-DIVIDEND> 0.304
<PER-SHARE-DISTRIBUTIONS> 1.550
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 21.20
<EXPENSE-RATIO> 0.24
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 062
<NAME> VANGUARD SMALL-CAP INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> JAN-01-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 2986293
<INVESTMENTS-AT-VALUE> 3228056
<RECEIVABLES> 33117
<ASSETS-OTHER> 558
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 3261731
<PAYABLE-FOR-SECURITIES> 20743
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 208632
<TOTAL-LIABILITIES> 229375
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 2769161
<SHARES-COMMON-STOCK> 12467
<SHARES-COMMON-PRIOR> 5762
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 641
<ACCUMULATED-NET-GAINS> 14857
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 248979
<NET-ASSETS> 264277
<DIVIDEND-INCOME> 38503
<INTEREST-INCOME> 5515
<OTHER-INCOME> 2866
<EXPENSES-NET> 6682
<NET-INVESTMENT-INCOME> 40202
<REALIZED-GAINS-CURRENT> 199544
<APPREC-INCREASE-CURRENT> (318857)
<NET-CHANGE-FROM-OPS> (79111)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 3153
<DISTRIBUTIONS-OF-GAINS> 14670
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 6477
<NUMBER-OF-SHARES-REDEEMED> 385
<SHARES-REINVESTED> 613
<NET-CHANGE-IN-ASSETS> 243062
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 18730
<OVERDISTRIB-NII-PRIOR> 381
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 100
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 6686
<AVERAGE-NET-ASSETS> 197759
<PER-SHARE-NAV-BEGIN> 23.75
<PER-SHARE-NII> 0.336
<PER-SHARE-GAIN-APPREC> (1.007)
<PER-SHARE-DIVIDEND> 0.329
<PER-SHARE-DISTRIBUTIONS> 1.550
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 21.20
<EXPENSE-RATIO> 0.12
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 071
<NAME> VANGUARD MID-CAP INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> APR-20-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 232879
<INVESTMENTS-AT-VALUE> 241691
<RECEIVABLES> 33858
<ASSETS-OTHER> 42
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 275591
<PAYABLE-FOR-SECURITIES> 30190
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1056
<TOTAL-LIABILITIES> 31246
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 220564
<SHARES-COMMON-STOCK> 19066
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 29
<ACCUMULATED-NET-GAINS> 14760
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 9050
<NET-ASSETS> 205657
<DIVIDEND-INCOME> 1184
<INTEREST-INCOME> 165
<OTHER-INCOME> 9
<EXPENSES-NET> 215
<NET-INVESTMENT-INCOME> 1143
<REALIZED-GAINS-CURRENT> 15845
<APPREC-INCREASE-CURRENT> 9050
<NET-CHANGE-FROM-OPS> 26038
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 962
<DISTRIBUTIONS-OF-GAINS> 907
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 20969
<NUMBER-OF-SHARES-REDEEMED> 2058
<SHARES-REINVESTED> 155
<NET-CHANGE-IN-ASSETS> 244345
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 20
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 215
<AVERAGE-NET-ASSETS> 113560
<PER-SHARE-NAV-BEGIN> 10.00
<PER-SHARE-NII> 0.053
<PER-SHARE-GAIN-APPREC> 0.840
<PER-SHARE-DIVIDEND> 0.053
<PER-SHARE-DISTRIBUTIONS> 0.050
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 10.79
<EXPENSE-RATIO> 0.25
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 072
<NAME> VANGUARD MID-CAP INDEX FUND-INSTITUTIONAL SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> MAY-20-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 232879
<INVESTMENTS-AT-VALUE> 241691
<RECEIVABLES> 33858
<ASSETS-OTHER> 42
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 275591
<PAYABLE-FOR-SECURITIES> 30190
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1056
<TOTAL-LIABILITIES> 31246
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 220564
<SHARES-COMMON-STOCK> 3586
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 29
<ACCUMULATED-NET-GAINS> 14760
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 9050
<NET-ASSETS> 38688
<DIVIDEND-INCOME> 1184
<INTEREST-INCOME> 165
<OTHER-INCOME> 9
<EXPENSES-NET> 215
<NET-INVESTMENT-INCOME> 1143
<REALIZED-GAINS-CURRENT> 15845
<APPREC-INCREASE-CURRENT> 9050
<NET-CHANGE-FROM-OPS> 26038
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 210
<DISTRIBUTIONS-OF-GAINS> 178
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 3559
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 27
<NET-CHANGE-IN-ASSETS> 244345
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 20
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 215
<AVERAGE-NET-ASSETS> 25293
<PER-SHARE-NAV-BEGIN> 10.03
<PER-SHARE-NII> 0.055
<PER-SHARE-GAIN-APPREC> 0.814
<PER-SHARE-DIVIDEND> 0.059
<PER-SHARE-DISTRIBUTIONS> 0.050
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 10.79
<EXPENSE-RATIO> 0.12
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 081
<NAME> VANGUARD SMALL-CAP VALUE INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> APR-20-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 131281
<INVESTMENTS-AT-VALUE> 119913
<RECEIVABLES> 15221
<ASSETS-OTHER> 21
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 135155
<PAYABLE-FOR-SECURITIES> 19053
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 3537
<TOTAL-LIABILITIES> 22590
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 123517
<SHARES-COMMON-STOCK> 12885
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 66
<ACCUMULATED-NET-GAINS> 482
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (11368)
<NET-ASSETS> 112565
<DIVIDEND-INCOME> 642
<INTEREST-INCOME> 103
<OTHER-INCOME> 33
<EXPENSES-NET> 139
<NET-INVESTMENT-INCOME> 639
<REALIZED-GAINS-CURRENT> 482
<APPREC-INCREASE-CURRENT> (11368)
<NET-CHANGE-FROM-OPS> (10247)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 705
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 15327
<NUMBER-OF-SHARES-REDEEMED> 2516
<SHARES-REINVESTED> 74
<NET-CHANGE-IN-ASSETS> 112565
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 20
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 139
<AVERAGE-NET-ASSETS> 80848
<PER-SHARE-NAV-BEGIN> 10.00
<PER-SHARE-NII> 0.045
<PER-SHARE-GAIN-APPREC> (1.250)
<PER-SHARE-DIVIDEND> 0.055
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 8.74
<EXPENSE-RATIO> 0.25
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000036405
<NAME> VANGUARD INDEX FUNDS
<SERIES>
<NUMBER> 091
<NAME> VANGUARD SMALL-CAP GROWTH INDEX FUND-INVESTOR SHARES
<MULTIPLIER> 1000
<CURRENCY> US
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-START> APR-20-1998
<PERIOD-END> DEC-31-1998
<EXCHANGE-RATE> 1
<INVESTMENTS-AT-COST> 85766
<INVESTMENTS-AT-VALUE> 91324
<RECEIVABLES> 12618
<ASSETS-OTHER> 14
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 103956
<PAYABLE-FOR-SECURITIES> 11177
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2661
<TOTAL-LIABILITIES> 13838
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 90155
<SHARES-COMMON-STOCK> 9451
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 28
<ACCUMULATED-NET-GAINS> (5567)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 5558
<NET-ASSETS> 90118
<DIVIDEND-INCOME> 226
<INTEREST-INCOME> 88
<OTHER-INCOME> 38
<EXPENSES-NET> 99
<NET-INVESTMENT-INCOME> 253
<REALIZED-GAINS-CURRENT> (5567)
<APPREC-INCREASE-CURRENT> 5558
<NET-CHANGE-FROM-OPS> 244
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 281
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10819
<NUMBER-OF-SHARES-REDEEMED> 1393
<SHARES-REINVESTED> 25
<NET-CHANGE-IN-ASSETS> 90118
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 20
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 99
<AVERAGE-NET-ASSETS> 57505
<PER-SHARE-NAV-BEGIN> 10.00
<PER-SHARE-NII> 0.03
<PER-SHARE-GAIN-APPREC> (0.47)
<PER-SHARE-DIVIDEND> 0.03
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.53
<EXPENSE-RATIO> 0.25
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>