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SIGNATURE JOHN J. ARTHUR
TITLE SR VP & TREASURER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Company Prime Portfolio Institutional Shares August 31, 1998
annual report.
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<NAME> SHORT TERM INVESTMENTS COMPANY
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WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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<LEGEND>
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<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Company Prime Portfolio Cash Management Shares August 31, 1998
annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS COMPANY
<SERIES>
<NUMBER> 1
<NAME> PRIME PORTFOLIO CASH MANAGEMENT SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 7873831856
<INVESTMENTS-AT-VALUE> 7873831856
<RECEIVABLES> 1435014
<ASSETS-OTHER> 561014
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 7875827884
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 36530041
<TOTAL-LIABILITIES> 36530041
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 7839304181
<SHARES-COMMON-STOCK> 7839304181
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
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<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
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<NET-ASSETS> 7839297843
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 433045612
<OTHER-INCOME> 0
<EXPENSES-NET> (9467209)
<NET-INVESTMENT-INCOME> 423578403
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 423578403
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (423578403)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 90498738700
<NUMBER-OF-SHARES-REDEEMED> (89596647368)
<SHARES-REINVESTED> 82495877
<NET-CHANGE-IN-ASSETS> 984587209
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4251522
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 10621924
<AVERAGE-NET-ASSETS> 898943542
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.05
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<PER-SHARE-DIVIDEND> (0.05)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.17
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Company Prime Portfolio Resource Shares August 31, 1998
annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS COMPANY
<SERIES>
<NUMBER> 1
<NAME> PRIME PORTFOLIO RESOURCE SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 7873831856
<INVESTMENTS-AT-VALUE> 7873831856
<RECEIVABLES> 1435014
<ASSETS-OTHER> 561014
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 7875827884
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 36530041
<TOTAL-LIABILITIES> 36530041
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 7839304181
<SHARES-COMMON-STOCK> 7839304181
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
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<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 7839297843
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 433045612
<OTHER-INCOME> 0
<EXPENSES-NET> (9467209)
<NET-INVESTMENT-INCOME> 423578403
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 423578403
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (423578403)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 90498738700
<NUMBER-OF-SHARES-REDEEMED> (89596647368)
<SHARES-REINVESTED> 82495877
<NET-CHANGE-IN-ASSETS> 984587209
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4251522
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 10621924
<AVERAGE-NET-ASSETS> 360386719
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.05
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.05)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.25
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Co. Liquid Assets Portfolio Institutional Shares August 31,
1998 annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 5
<NAME> LIQUID ASSETS PORTFOLIO INSTITUTIONAL SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 3972024575
<INVESTMENTS-AT-VALUE> 3972024575
<RECEIVABLES> 55494043
<ASSETS-OTHER> 369591
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 4027888209
<PAYABLE-FOR-SECURITIES> 97467238
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 20807307
<TOTAL-LIABILITIES> 118274545
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 3910243129
<SHARES-COMMON-STOCK> 3910243129
<SHARES-COMMON-PRIOR> 4023590763
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (629465)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 3909613664
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 235786553
<OTHER-INCOME> 0
<EXPENSES-NET> (3823921)
<NET-INVESTMENT-INCOME> 231962632
<REALIZED-GAINS-CURRENT> 750940
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 232713572
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (231962632)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 100169161624
<NUMBER-OF-SHARES-REDEEMED> (100338904663)
<SHARES-REINVESTED> 56395405
<NET-CHANGE-IN-ASSETS> (112596694)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1380405)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 6237470
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 8324392
<AVERAGE-NET-ASSETS> 3713280577
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.06
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.06)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.08
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Co. Liquid Assets Portfolio Private Shares August 31,
1998 annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 5
<NAME> LIQUID ASSETS PORTFOLIO PRIVATE SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 3972024575
<INVESTMENTS-AT-VALUE> 3972024575
<RECEIVABLES> 55494043
<ASSETS-OTHER> 369591
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 4027888209
<PAYABLE-FOR-SECURITIES> 97467238
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 20807307
<TOTAL-LIABILITIES> 118274545
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 3910243129
<SHARES-COMMON-STOCK> 3910243129
<SHARES-COMMON-PRIOR> 4023590763
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (629465)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 3909613664
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 235786553
<OTHER-INCOME> 0
<EXPENSES-NET> (3823921)
<NET-INVESTMENT-INCOME> 231962632
<REALIZED-GAINS-CURRENT> 750940
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 232713572
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (231962632)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 100169161624
<NUMBER-OF-SHARES-REDEEMED> (100338904663)
<SHARES-REINVESTED> 56395405
<NET-CHANGE-IN-ASSETS> (112596694)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1380405)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 6237470
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 8324392
<AVERAGE-NET-ASSETS> 66254739
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.05
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.05)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.38
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Co. Liquid Assets Portfolio Cash Management Shares August 31,
1998 annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 5
<NAME> LIQUID ASSETS PORTFOLIO CASH MANAGEMENT SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 3972024575
<INVESTMENTS-AT-VALUE> 3972024575
<RECEIVABLES> 55494043
<ASSETS-OTHER> 369591
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 4027888209
<PAYABLE-FOR-SECURITIES> 97467238
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 20807307
<TOTAL-LIABILITIES> 118274545
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 3910243129
<SHARES-COMMON-STOCK> 3910243129
<SHARES-COMMON-PRIOR> 4023590763
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (629465)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 3909613664
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 235786553
<OTHER-INCOME> 0
<EXPENSES-NET> (3823921)
<NET-INVESTMENT-INCOME> 231962632
<REALIZED-GAINS-CURRENT> 750940
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 232713572
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (231962632)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 100169161624
<NUMBER-OF-SHARES-REDEEMED> (100338904663)
<SHARES-REINVESTED> 56395405
<NET-CHANGE-IN-ASSETS> (112596694)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1380405)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 6237470
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 8324392
<AVERAGE-NET-ASSETS> 292425889
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.06
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.06)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.16
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information from the Short Term
Investments Co. Liquid Assets Portfolio Morgan Stanley Shares August 31,
1998 annual report.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 5
<NAME> LIQUID ASSETS PORTFOLIO MORGAN STANLEY SHARES
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> AUG-31-1998
<INVESTMENTS-AT-COST> 3972024575
<INVESTMENTS-AT-VALUE> 3972024575
<RECEIVABLES> 55494043
<ASSETS-OTHER> 369591
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 4027888209
<PAYABLE-FOR-SECURITIES> 97467238
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 20807307
<TOTAL-LIABILITIES> 118274545
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 3910243129
<SHARES-COMMON-STOCK> 3910243129
<SHARES-COMMON-PRIOR> 4023590763
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (629465)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 3909613664
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 235786553
<OTHER-INCOME> 0
<EXPENSES-NET> (3823921)
<NET-INVESTMENT-INCOME> 231962632
<REALIZED-GAINS-CURRENT> 750940
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 232713572
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (231962632)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 100169161624
<NUMBER-OF-SHARES-REDEEMED> (100338904663)
<SHARES-REINVESTED> 56395405
<NET-CHANGE-IN-ASSETS> (112596694)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1380405)
<OVERDISTRIB-NII-PRIOR> 0
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<GROSS-ADVISORY-FEES> 6237470
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<GROSS-EXPENSE> 8324392
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<PER-SHARE-DIVIDEND> (0.05)
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.28
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<AVG-DEBT-PER-SHARE> 0
</TABLE>
