WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

 

<ARTICLE> 6
<CIK> 0000897802
<NAME> INSURED MUNICIPAL INCOME FUND INC.
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                                12-MOS
<FISCAL-YEAR-END>                                             MAR-31-2000
<PERIOD-START>                                                APR-01-1999
<PERIOD-END>                                                  MAR-31-2000
<INVESTMENTS-AT-COST>                                             432,311
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<SHARES-COMMON-STOCK>                                              20,628
<SHARES-COMMON-PRIOR>                                              20,628
<ACCUMULATED-NII-CURRENT>                                           1,058
<OVERDISTRIBUTION-NII>                                                  0
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<DIVIDEND-INCOME>                                                       0
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<OTHER-INCOME>                                                          0
<EXPENSES-NET>                                                    (4,383)
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<REALIZED-GAINS-CURRENT>                                             (22)
<APPREC-INCREASE-CURRENT>                                        (21,742)
<NET-CHANGE-FROM-OPS>                                               (318)
<EQUALIZATION>                                                          0
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