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<PAGE> PAGE 2
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SIGNATURE PAUL BUCAVALAS
TITLE MANAGING DIRECTOR
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Health Sciences Trust
</LEGEND>
<SERIES>
<NUMBER> 3
<NAME> CLASS A
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<PERIOD-END> AUG-31-1999
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<DISTRIBUTIONS-OF-GAINS> (209,438,189)
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[AVG-DEBT-OUTSTANDING] 0
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</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Health Sciences Trust
</LEGEND>
<SERIES>
<NUMBER> 3
<NAME> CLASS B
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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>
Putnam Health Sciences Trust
</LEGEND>
<SERIES>
<NUMBER> 3
<NAME> CLASS C
<S> <C>
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<GROSS-EXPENSE> 60,733,358
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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>
Putnam Health Sciences Trust
</LEGEND>
<SERIES>
<NUMBER> 3
<NAME> CLASS M
<S> <C>
<PERIOD-TYPE> ANNUAL
<FISCAL-YEAR-END> AUG-31-1999
<PERIOD-END> AUG-31-1999
<INVESTMENTS-AT-COST> 3,986,704,054
<INVESTMENTS-AT-VALUE> 5,196,586,869
<RECEIVABLES> 46,515,851
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<SHARES-COMMON-PRIOR> 1,071,675
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<DISTRIBUTIONS-OF-GAINS> (6,108,803)
<DISTRIBUTIONS-OTHER> (36,651)
<NUMBER-OF-SHARES-SOLD> 933,321
<NUMBER-OF-SHARES-REDEEMED> (501,896)
<SHARES-REINVESTED> 91,148
<NET-CHANGE-IN-ASSETS> 1,536,809,861
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 355,587,068
<OVERDISTRIB-NII-PRIOR> 0
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<GROSS-ADVISORY-FEES> 25,715,677
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<GROSS-EXPENSE> 60,733,358
<AVERAGE-NET-ASSETS> 83,753,086
<PER-SHARE-NAV-BEGIN> 52.87
<PER-SHARE-NII> (.37)
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[AVG-DEBT-PER-SHARE] 0
</TABLE>
REPORT OF INDEPENDENT ACCOUNTANTS
To the Board of Trustees of Putnam Health Sciences Trust:
In planning and performing our audit of the financial statements
of Putnam Health Sciences Trust for the year ended August 31,
1999, we considered its internal control, including control
activities for safeguarding securities, in order to determine our
auditing procedures for the purpose of expressing our opinion on
the financial statements and to comply with the requirements of
Form N-SAR, not to provide assurance on internal control.
The management of Putnam Health Sciences Trust is responsible for
establishing and maintaining internal control. In fulfilling
this responsibility, estimates and judgments by management are
required to assess the expected benefits and related costs of
controls. Generally, controls that are relevant to an audit
pertain to the entity's objective of preparing financial
statements for external purposes that are fairly presented in
conformity with generally accepted accounting principles. Those
controls include the safeguarding of assets against unauthorized
acquisition, use or disposition.
Because of inherent limitations in internal controls, errors or
fraud may occur and may not be detected. Also, projection of any
evaluation of internal control to future periods is subject to
the risk that it may become inadequate because of changes in
conditions or that the effectiveness of the design and operation
may deteriorate.
Our consideration of internal control would not necessarily
disclose all matters in internal control that might be material
weaknesses under standards established by the American Institute
of Certified Public Accountants. A material weakness is a
condition in which the design or operation of one or more of the
internal control components does not reduce to a relatively low
level the risk that misstatements caused by errors or fraud in
amounts that would be material in relation to the financial
statements being audited may occur and not be detected within a
timely period by employees in the normal course of performing
their assigned functions. However, we noted no matters involving
internal control and its operation, including controls for
safeguarding securities, that we consider to be material
weaknesses as defined above as of August 31, 1999.
This report is intended solely for the information and use of
management and the Board of Trustees and the Securities and
Exchange Commission and is not intended to be and should not be
used by anyone other than these specified parties.
PricewaterhouseCoopers LLP
Boston, Massachusetts
October 11, 1999
