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SIGNATURE JOHN ARTHUR
TITLE TREASURER
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<NAME> SHORT-TERM INVESTMENTS CO.
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<LEGEND>
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<NAME> SHORT-TERM INVESTMENTS CO.
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<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .37
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Prime Portfolio Institutional Class for the semi-annual
period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 1
<NAME> PRIME PORTFOLIO INSTITUTIONAL CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 6832527164
<INVESTMENTS-AT-VALUE> 6832527164
<RECEIVABLES> 457261
<ASSETS-OTHER> 910729
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 6833895154
<PAYABLE-FOR-SECURITIES> 39809178
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 31116826
<TOTAL-LIABILITIES> 70926004
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 6762975488
<SHARES-COMMON-STOCK> 6762975488
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 6762969150
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 214733746
<OTHER-INCOME> 0
<EXPENSES-NET> (4545369)
<NET-INVESTMENT-INCOME> 210188377
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 210188377
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (210188377)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 46947977626
<NUMBER-OF-SHARES-REDEEMED> (47073385950)
<SHARES-REINVESTED> 33666840
<NET-CHANGE-IN-ASSETS> (91741484)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2100407
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5062101
<AVERAGE-NET-ASSETS> 6252534746
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .09
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Prime Portfolio Private Investment Class for the
semi-annual period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 2
<NAME> PRIME PORTFOLIO PRIVATE INVESTMENTS CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 6832527164
<INVESTMENTS-AT-VALUE> 6832527164
<RECEIVABLES> 457261
<ASSETS-OTHER> 910729
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 6833895154
<PAYABLE-FOR-SECURITIES> 39809178
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 31116826
<TOTAL-LIABILITIES> 70926004
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 6762975488
<SHARES-COMMON-STOCK> 6762975488
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 6762969150
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 214733746
<OTHER-INCOME> 0
<EXPENSES-NET> (4545369)
<NET-INVESTMENT-INCOME> 210188377
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 210188377
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (210188377)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 46947977626
<NUMBER-OF-SHARES-REDEEMED> (47073385950)
<SHARES-REINVESTED> 33666840
<NET-CHANGE-IN-ASSETS> (91741484)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2100407
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5062101
<AVERAGE-NET-ASSETS> 264241422
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .39
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Prime Portfolio Resource Class for the semi-annual
period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 8
<NAME> PRIME PORTFOLIO RESOURCE CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 6832527164
<INVESTMENTS-AT-VALUE> 6832527164
<RECEIVABLES> 457261
<ASSETS-OTHER> 910729
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 6833895154
<PAYABLE-FOR-SECURITIES> 39809178
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 31116826
<TOTAL-LIABILITIES> 70926004
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 6762975488
<SHARES-COMMON-STOCK> 6762975488
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 6762969150
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 214733746
<OTHER-INCOME> 0
<EXPENSES-NET> (4545369)
<NET-INVESTMENT-INCOME> 210188377
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 210188377
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (210188377)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 46947977626
<NUMBER-OF-SHARES-REDEEMED> (47073385950)
<SHARES-REINVESTED> 33666840
<NET-CHANGE-IN-ASSETS> (91741484)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2100407
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5062101
<AVERAGE-NET-ASSETS> 205163569
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .25
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Prime Portfolio Personal Investment Class for the
semi-annual period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 3
<NAME> PRIME PORTFOLIO PERSONAL INVESTMENT CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 6832527164
<INVESTMENTS-AT-VALUE> 6832527164
<RECEIVABLES> 457261
<ASSETS-OTHER> 910729
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 6833895154
<PAYABLE-FOR-SECURITIES> 39809178
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 31116826
<TOTAL-LIABILITIES> 70926004
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 6762975488
<SHARES-COMMON-STOCK> 6762975488
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 6762969150
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 214733746
<OTHER-INCOME> 0
<EXPENSES-NET> (4545369)
<NET-INVESTMENT-INCOME> 210188377
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 210188377
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (210188377)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 46947977626
<NUMBER-OF-SHARES-REDEEMED> (47073385950)
<SHARES-REINVESTED> 33666840
<NET-CHANGE-IN-ASSETS> (91741484)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2100407
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5062101
<AVERAGE-NET-ASSETS> 110616291
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .59
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Prime Portfolio Cash Management Class for the
semi-annual period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 4
<NAME> PRIME PORTFOLIO CASH MANAGEMENT CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 6832527164
<INVESTMENTS-AT-VALUE> 6832527164
<RECEIVABLES> 457261
<ASSETS-OTHER> 910729
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 6833895154
<PAYABLE-FOR-SECURITIES> 39809178
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 31116826
<TOTAL-LIABILITIES> 70926004
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 6762975488
<SHARES-COMMON-STOCK> 6762975488
<SHARES-COMMON-PRIOR> 6854716972
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (6338)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 6762969150
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 214733746
<OTHER-INCOME> 0
<EXPENSES-NET> (4545369)
<NET-INVESTMENT-INCOME> 210188377
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 210188377
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (210188377)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 46947977626
<NUMBER-OF-SHARES-REDEEMED> (47073385950)
<SHARES-REINVESTED> 33666840
<NET-CHANGE-IN-ASSETS> (91741484)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (6338)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2100407
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5062101
<AVERAGE-NET-ASSETS> 798698883
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .17
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information for the Short-Term
Investments Co. Liquid Assets Portfolio Institutional Class for the semi-annual
period ended February 28, 1998.
</LEGEND>
<CIK> 0000914638
<NAME> SHORT-TERM INVESTMENTS CO.
<SERIES>
<NUMBER> 5
<NAME> LIQUID ASSETS PORTFOLIO INSTITUTIONAL CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> AUG-31-1998
<PERIOD-END> FEB-28-1998
<INVESTMENTS-AT-COST> 4681412324
<INVESTMENTS-AT-VALUE> 4681412324
<RECEIVABLES> 7530415
<ASSETS-OTHER> 531204
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 4689473943
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 17909204
<TOTAL-LIABILITIES> 17909204
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4672372431
<SHARES-COMMON-STOCK> 4672372431
<SHARES-COMMON-PRIOR> 4023590763
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (807692)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 4671564739
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 112477098
<OTHER-INCOME> 0
<EXPENSES-NET> (1755116)
<NET-INVESTMENT-INCOME> 110721982
<REALIZED-GAINS-CURRENT> 572713
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 111294695
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (110721982)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 47893901134
<NUMBER-OF-SHARES-REDEEMED> (47267676180)
<SHARES-REINVESTED> 22556714
<NET-CHANGE-IN-ASSETS> 649354381
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (1380405)
<OVERDISTRIB-NII-PRIOR> 0
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<GROSS-EXPENSE> 3905992
<AVERAGE-NET-ASSETS> 3643174428
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .03
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<PER-SHARE-DIVIDEND> (.03)
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .07
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</TABLE>
