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001 A000000 JOHN HANCOCK BANK AND THRIFT OPPORTUNITY FUND
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<PAGE> PAGE 2
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SIGNATURE SUSAN S. NEWTON
TITLE VICE PRESIDENT
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER> 000
<NAME> JOHN HANCOCK BANK AND THRIFT OPPORTUNITY FUND
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> OCT-31-1998
<PERIOD-START> NOV-01-1997
<PERIOD-END> APR-30-1998
<INVESTMENTS-AT-COST> 480,195,392
<INVESTMENTS-AT-VALUE> 1,218,667,118
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<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,339,222
<TOTAL-LIABILITIES> 7,535,836
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 435,267,021
<SHARES-COMMON-STOCK> 88,400,000
<SHARES-COMMON-PRIOR> 88,400,000
<ACCUMULATED-NII-CURRENT> 4,737,338
<OVERDISTRIBUTION-NII> 0
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<OVERDISTRIBUTION-GAINS> 0
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<NET-ASSETS> 1,222,361,325
<DIVIDEND-INCOME> 11,466,776
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<OTHER-INCOME> 0
<EXPENSES-NET> 8,065,903
<NET-INVESTMENT-INCOME> 6,110,704
<REALIZED-GAINS-CURRENT> 43,879,722
<APPREC-INCREASE-CURRENT> 175,985,947
<NET-CHANGE-FROM-OPS> 225,976,373
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 12,375,469
<DISTRIBUTIONS-OF-GAINS> 52,637,780
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</TABLE>
