<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains Summary Financial Information extracted from the Form
N-SAR and the financial statements and is qualified in its entirety by
references to such documents.
</LEGEND>
<SERIES>
   <NUMBER> 012
   <NAME> NUVEEN INTERMEDIATE DURATION MUNI BOND FUND - CLASS B
<MULTIPLIER> 1000

<S>                             <C>
<PERIOD-TYPE>                   12-MOS
<FISCAL-YEAR-END>                          APR-30-2000
<PERIOD-START>                             MAY-01-1999
<PERIOD-END>                               APR-30-2000
<INVESTMENTS-AT-COST>                          2533954
<INVESTMENTS-AT-VALUE>                         2590994
<RECEIVABLES>                                    54126
<ASSETS-OTHER>                                    5926
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                                 2651046
<PAYABLE-FOR-SECURITIES>                          8586
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                        12100
<TOTAL-LIABILITIES>                              20686
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                       2570814
<SHARES-COMMON-STOCK>                             1297
<SHARES-COMMON-PRIOR>                             1054
<ACCUMULATED-NII-CURRENT>                         2643
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                          (137)
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                         57040
<NET-ASSETS>                                   2630360
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                               160658
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   16737
<NET-INVESTMENT-INCOME>                         143921
<REALIZED-GAINS-CURRENT>                         (110)
<APPREC-INCREASE-CURRENT>                     (203225)
<NET-CHANGE-FROM-OPS>                          (59414)
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                          488
<DISTRIBUTIONS-OF-GAINS>                            16
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                            720
<NUMBER-OF-SHARES-REDEEMED>                        503
<SHARES-REINVESTED>                                 27
<NET-CHANGE-IN-ASSETS>                        (341350)
<ACCUMULATED-NII-PRIOR>                           1260
<ACCUMULATED-GAINS-PRIOR>                         3530
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                            12494
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                                  16861
<AVERAGE-NET-ASSETS>                             11680
<PER-SHARE-NAV-BEGIN>                             9.57
<PER-SHARE-NII>                                    .39
<PER-SHARE-GAIN-APPREC>                          (.66)
<PER-SHARE-DIVIDEND>                             (.38)
<PER-SHARE-DISTRIBUTIONS>                        (.01)
<RETURNS-OF-CAPITAL>                                 0
<PER-SHARE-NAV-END>                               8.91
<EXPENSE-RATIO>                                   1.54


</TABLE>