Payment Date: 05/25/00
------------------------------------------------------------
BA MORTGAGE SECURITIES, INC.
Mortgage Pass-Through Certificates, Series 1998-4
BANK OF AMERICA, FSB, MASTER SERVICER
------------------------------------------------------------
<TABLE>
<CAPTION>
Class Information Current Payment Information
----------------------------------------------------------------------------------------------------------------------------------
Beginning Pass Thru Principal Interest Total Principal Interest
Type Class Code Name Cert. Bal. Rate Dist. Amt. Dist. Amt. Dist. Losses Shortfalls
----------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Senior IA-1 13,407,946.40 6.650000% 320,514.08 74,302.37 394,816.45 0.00 0.00
IA-2 19,848,293.47 6.250000% 637,021.72 103,376.53 740,398.25 0.00 0.00
IA-3 6,800,000.00 6.650000% 0.00 37,683.33 37,683.33 0.00 0.00
IA-4 23,800,000.00 6.600000% 0.00 130,900.00 130,900.00 0.00 0.00
IA-5 44,329,882.75 6.500000% 701,124.54 240,120.20 941,244.74 0.00 0.00
IA-6 3,940,357.34 6.750000% 0.00 22,164.51 22,164.51 0.00 0.00
IA-7 61,961,793.61 6.650000% 948,171.43 343,371.61 1,291,543.03 0.00 0.00
IA-8 11,933,382.47 7.009594% 182,610.79 69,706.80 252,317.59 0.00 0.00
IA-9 4,130,786.24 7.500000% 63,211.43 25,817.41 89,028.84 0.00 0.00
IA-10 0.00 6.750000% 0.00 0.00 0.00 0.00 0.00
IA-11 3,375,037.05 6.750000% 0.00 0.00 0.00 0.00 0.00
IA-12 59,500,000.00 6.750000% 0.00 334,687.50 334,687.50 0.00 0.00
IIA-1 24,737,643.14 6.500000% 668,408.15 133,995.57 802,403.72 0.00 0.00
IIA-2 25,828,000.00 6.500000% 0.00 139,901.67 139,901.67 0.00 0.00
IIA-3 19,183,152.57 6.500000% 0.00 103,908.74 103,908.74 0.00 0.00
IIA-4 0.00 6.500000% 0.00 0.00 0.00 0.00 0.00
IIA-5 0.00 6.500000% 0.00 0.00 0.00 0.00 0.00
IIA-6 24,116,915.39 6.500000% 97,721.40 130,633.29 228,354.69 0.00 0.00
I-X-1 0.00 0.245862% 0.00 0.00 0.00 0.00 0.00
I-X-2 102,534,403.33 0.245862% 0.00 21,007.78 21,007.78 0.00 0.00
I-X-3 70,972,000.00 0.245862% 0.00 14,541.11 14,541.11 0.00 0.00
I-X-4 73,192,498.91 0.245862% 0.00 14,996.06 14,996.06 0.00 0.00
II-X 832,073.63 6.500000% 0.00 4,507.07 4,507.07 0.00 0.00
I-PO 100,371.51 0.000000% 110.76 0.00 110.76 0.00 0.00
II-PO 239,869.53 0.000000% 1,337.61 0.00 1,337.61 0.00 0.00
Residual R-I 0.00 6.750000% 0.00 0.00 0.00 0.00 0.00
R-II 0.00 6.500000% 0.00 0.00 0.00 0.00 0.00
R-III 0.00 6.750000% 0.00 0.00 0.00 0.00 0.00
----------------------------------------------------------------------------------------------------------------------------------
Subordinate IM 6,779,333.73 6.750000% 6,396.99 38,133.75 44,530.74 0.00 0.00
IB-1 3,114,643.19 6.750000% 2,938.98 17,519.87 20,458.85 0.00 0.00
IB-2 1,649,159.86 6.750000% 1,556.15 9,276.52 10,832.67 0.00 0.00
IB-3 1,282,789.02 6.750000% 1,210.44 7,215.69 8,426.13 0.00 0.00
IB-4 916,418.19 6.750000% 864.73 5,154.85 6,019.59 0.00 0.00
IB-5 916,415.25 6.750000% 864.73 5,154.84 6,019.57 0.00 0.00
IIM 1,144,625.90 6.500000% 4,638.01 6,200.06 10,838.06 0.00 0.00
IIB-1 421,118.44 6.500000% 1,706.37 2,281.06 3,987.42 0.00 0.00
IIB-2 301,461.44 6.500000% 1,221.52 1,632.92 2,854.43 0.00 0.00
IIB-3 360,826.16 6.500000% 1,462.06 1,954.48 3,416.54 0.00 0.00
IIB-4 180,876.87 6.500000% 732.91 979.75 1,712.66 0.00 0.00
IIB-5 301,358.77 6.500000% 1,221.06 1,632.36 2,853.42 0.00 0.00
----------------------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------------
Totals - - 360,662,100.96 - 3,645,045.86 2,042,757.69 5,687,803.55 - -
----------------------------------------------------------------------------------------------------------------------------------
Class Information
--------------------------------------------------------------------------------
Ending Cert. Unpaid
Type Class Code Name Notional Bal. Interest
--------------------------------------------------------------------------------
Senior IA-1 13,087,432.32 0.00
IA-2 19,211,271.75 0.00
IA-3 6,800,000.00 0.00
IA-4 23,800,000.00 0.00
IA-5 43,628,758.21 0.00
IA-6 3,862,454.62 0.00
IA-7 61,013,622.19 0.00
IA-8 11,750,771.68 0.00
IA-9 4,067,574.81 0.00
IA-10 0.00 0.00
IA-11 3,394,021.63 0.00
IA-12 59,500,000.00 0.00
IIA-1 24,069,234.99 0.00
IIA-2 25,828,000.00 0.00
IIA-3 19,183,152.57 0.00
IIA-4 0.00 0.00
IIA-5 0.00 0.00
IIA-6 24,019,193.99 0.00
I-X-1 0.00 0.00
I-X-2 100,950,335.98 0.00
I-X-3 70,972,000.00 0.00
I-X-4 71,950,274.17 0.00
II-X 816,618.59 0.00
I-PO 100,260.75 0.00
II-PO 238,531.93 0.00
Residual R-I 0.00 0.00
R-II 0.00 0.00
R-III 0.00 0.00
--------------------------------------------------------------------------------
Subordinate IM 6,772,936.74 0.00
IB-1 3,111,704.20 0.00
IB-2 1,647,603.71 0.00
IB-3 1,281,578.58 0.00
IB-4 915,553.46 0.00
IB-5 915,550.52 0.00
IIM 1,139,987.90 0.00
IIB-1 419,412.08 0.00
IIB-2 300,239.92 0.00
IIB-3 359,364.10 0.00
IIB-4 180,143.95 0.00
IIB-5 300,137.70 0.00
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Totals - - 357,036,039.69 -
--------------------------------------------------------------------------------
</TABLE>
<PAGE>
Payment Date: 05/25/00
------------------------------------------------------------
BA MORTGAGE SECURITIES, INC.
Mortgage Pass-Through Certificates, Series 1998-4
BANK OF AMERICA, FSB, MASTER SERVICER
------------------------------------------------------------
<TABLE>
<CAPTION>
Class Information Current Payment Information
Factors per $1,000
------------------------------------------------------------------------------------------------------------------------
Beginning Pass Thru CUSIP Principal Interest Ending Cert./
Type Class Code Name Cert. Bal.(Face) Rate Numbers Dist. Dist. Notional Bal.
------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C>
------------------------------------------------------------------------------------------------------------------------
Senior IA-1 13,407,946.40 6.650000% 055240GY5 20.032130 4.643898 817.964520
IA-2 19,848,293.47 6.250000% 055240GZ2 25.480869 4.135061 768.450870
IA-3 6,800,000.00 6.650000% 055240HA6 0.000000 5.541667 1,000.000000
IA-4 23,800,000.00 6.600000% 055240HB4 0.000000 5.500000 1,000.000000
IA-5 44,329,882.75 6.500000% 055240HC2 14.022491 4.802404 872.575164
IA-6 3,940,357.34 6.750000% 055240HD0 0.000000 4.849610 845.107642
IA-7 61,961,793.61 6.650000% 055240HE8 7.218389 2.614073 464.494098
IA-8 11,933,382.47 7.009594% 055240HF5 7.218389 2.755427 464.494098
IA-9 4,130,786.24 7.500000% 055240HG3 7.218389 2.948203 464.494097
IA-10 0.00 6.750000% 055240HH1 0.000000 0.000000 0.000000
IA-11 3,375,037.05 6.750000% 055240HJ7 0.000000 0.000000 1,131.340545
IA-12 59,500,000.00 6.750000% 055240HK4 0.000000 5.625000 1,000.000000
IIA-1 24,737,643.14 6.500000% 055240HL2 24.755857 4.962799 891.453148
IIA-2 25,828,000.00 6.500000% 055240HM0 0.000000 5.416667 1,000.000000
IIA-3 19,183,152.57 6.500000% 055240HN8 0.000000 2.244249 414.322950
IIA-4 0.00 6.500000% 055240HP3 0.000000 0.000000 0.000000
IIA-5 0.00 6.500000% 055240HQ1 0.000000 0.000000 0.000000
IIA-6 24,116,915.39 6.500000% 055240HR9 3.758515 5.024357 923.815154
I-X-1 0.00 0.245862% 055240HS7 0.000000 0.000000 0.000000
I-X-2 102,534,403.33 0.245862% 055240HT5 0.000000 0.183737 882.926952
I-X-3 70,972,000.00 0.245862% 055240HU2 0.000000 0.204885 1,000.000000
I-X-4 73,192,498.91 0.245862% 055240HV0 0.000000 0.093866 450.362573
II-X 832,073.63 6.500000% 055240HW8 0.000000 3.361385 609.036892
I-PO 100,371.51 0.000000% 055240HX6 1.076195 0.000000 974.199871
II-PO 239,869.53 0.000000% 055240HY4 4.589338 0.000000 818.403641
Residual R-I 0.00 6.750000% 055240JF3 0.000000 0.000000 0.000000
R-II 0.00 6.500000% 055240JG1 0.000000 0.000000 0.000000
R-III 0.00 6.750000% 055240JH9 0.000000 0.000000 0.000000
------------------------------------------------------------------------------------------------------------------------
Subordinate IM 6,779,333.73 6.750000% 055240HZ1 0.926831 5.525029 981.300600
IB-1 3,114,643.19 6.750000% 055240JA4 0.926831 5.525029 981.300600
IB-2 1,649,159.86 6.750000% 055240JB2 0.926831 5.525029 981.300603
IB-3 1,282,789.02 6.750000% 055240JJ5 0.926831 5.525029 981.300597
IB-4 916,418.19 6.750000% 055240JK2 0.926831 5.525029 981.300598
IB-5 916,415.25 6.750000% 055240JL0 0.926831 5.525029 981.300603
IIM 1,144,625.90 6.500000% 055240JC0 3.758515 5.024357 923.815150
IIB-1 421,118.44 6.500000% 055240JD8 3.758515 5.024357 923.815146
IIB-2 301,461.44 6.500000% 055240JE6 3.758515 5.024357 923.815143
IIB-3 360,826.16 6.500000% 055240JM8 3.758515 5.024357 923.815161
IIB-4 180,876.87 6.500000% 055240JN6 3.758515 5.024357 923.815152
IIB-5 301,358.77 6.500000% 055240JP1 3.758401 5.024362 923.816144
------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------
Totals - - 360,662,100.96 - - - - -
------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------
</TABLE>
<PAGE>
------------------------------------------------------------
BA MORTGAGE SECURITIES, INC.
Mortgage Pass-Through Certificates, Series 1998-4
BANK OF AMERICA, FSB, MASTER SERVICER
------------------------------------------------------------
--------------------------------------------------------------------------------
COLLATERAL INFORMATION
--------------------------------------------------------------------------------
Total
-----
Prin balance 260,998,641.34 96,037,398.92 357,036,040.26
Loan count 819 291 1110
Avg loan rate 7.427089% 7.024261% 7.32
Prepay amount 2,598,639.72 386,133.68 2,984,773.40
--------------------------------------------------------------------------------
FEES AND ADVANCES
--------------------------------------------------------------------------------
Total
-----
Master serv fees 90,374.20 38,521.69 128,895.89
Sub servicer fees 0.00 0.00 0.00
Trustee fees 989.42 363.06 1,352.48
Agg advances N/A N/A N/A
Adv this period 0.00 0.00 0.00
--------------------------------------------------------------------------------
LOSSES & INSURANCE COVERAGES
--------------------------------------------------------------------------------
Total
-----
Realized losses 0.00 0.00 0.00
Cumulative losses 0.00 0.00 0.00
Coverage Amounts Total
---------------- -----
Bankruptcy 0.00 0.00 0.00
Fraud 3,730,870.14 1,298,233.99 5,029,104.13
Special Hazard 3,068,101.55 1,736,057.80 4,804,159.35
Aggregate Certificate Information
-----------------------------------------------------------------------------
Class Aggregate Aggregate Aggregate
Type Percentage Prepay Pct. End Cert. Bal.
-----------------------------------------------------------------------------
Senior 95.190677% 100.000000% 343,293,074.14
-----------------------------------------------------------------------------
Junior 4.809323% 0.000000% 17,344,212.86
-----------------------------------------------------------------------------
--------------------------------------------------------------------------------
DELINQUENCY INFORMATION
--------------------------------------------------------------------------------
Period Loan Count Ending Stated Balance
------ ---------- ---------------------
30 to 59 days 0 0.00
60 to 89 days 0 0.00
90 or more 0 0.00
Foreclosure 0 0.00
Totals: 0 0.00
--------------------------------------------------------------------------------
<PAGE>
--------------------------------------------------------------------------------
REO INFORMATION
--------------------------------------------------------------------------------
REO Date Loan Number Ending Stated Balance Book Value
-------- ----------- --------------------- ----------
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
N/A # 0 N/A
Totals: 0 N/A
Current Total Outstanding Balance: 0.00
Current Total Outstanding Number of Loans: 0
<PAGE>
--------------------------------------------------------------------------------
OTHER INFORMATION
--------------------------------------------------------------------------------
Amount/Withdrawal Total/Ending Bal.
----------------- -----------------
Available remittance amount 5,687,803.55 5,687,803.55
Principal remittance amount 3,645,045.86 3,645,045.86
Interest remittance amount 2,042,757.69 2,042,757.69
