<PAGE> PAGE 1
000 B000000 12/31/1998
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<PAGE> PAGE 2
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<PAGE> PAGE 3
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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<PAGE> PAGE 8
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<PAGE> PAGE 9
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<PAGE> PAGE 10
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<PAGE> PAGE 11
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<PAGE> PAGE 12
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<PAGE> PAGE 13
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<PAGE> PAGE 14
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<PAGE> PAGE 15
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<PAGE> PAGE 16
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<PAGE> PAGE 17
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<PAGE> PAGE 18
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<PAGE> PAGE 19
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<PAGE> PAGE 20
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<PAGE> PAGE 21
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008 A000601 MACKAY-SHIELDS FINANCIAL CORPORATION
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<PAGE> PAGE 22
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050 000600 N
051 000600 N
052 000600 N
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<PAGE> PAGE 23
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067 000600 N
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070 B020600 N
070 C010600 N
070 C020600 N
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070 D020600 N
070 E010600 N
070 E020600 N
070 F010600 Y
070 F020600 N
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070 G020600 N
070 H010600 Y
070 H020600 N
070 I010600 N
070 I020600 N
070 J010600 Y
070 J020600 N
070 K010600 N
070 K020600 Y
070 L010600 Y
070 L020600 Y
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<PAGE> PAGE 24
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008 A000701 MACKAY-SHIELDS FINANCIAL CORPORATION
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<PAGE> PAGE 25
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048 K010700 0
048 K020700 0.000
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050 000700 N
051 000700 N
052 000700 N
053 A000700 N
058 A000700 N
059 000700 Y
060 A000700 Y
060 B000700 Y
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<PAGE> PAGE 26
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066 E000700 N
066 F000700 N
066 G000700 N
067 000700 N
068 A000700 N
068 B000700 N
069 000700 N
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070 F020700 N
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070 H010700 Y
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070 I010700 N
070 I020700 N
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070 J020700 N
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<PAGE> PAGE 27
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070 N010700 Y
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070 R010700 N
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008 D010801 PRINCETON
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008 D040801 6242
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<PAGE> PAGE 28
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<PAGE> PAGE 29
050 000800 N
051 000800 N
052 000800 N
053 A000800 Y
053 B000800 Y
053 C000800 N
058 A000800 N
059 000800 Y
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066 D000800 N
066 E000800 N
066 F000800 N
066 G000800 N
067 000800 N
068 A000800 N
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069 000800 Y
070 A010800 Y
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070 B020800 N
070 C010800 N
070 C020800 N
070 D010800 Y
070 D020800 N
070 E010800 N
070 E020800 N
070 F010800 Y
<PAGE> PAGE 30
070 F020800 Y
070 G010800 Y
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070 H020800 N
070 I010800 N
070 I020800 N
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070 K010800 N
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<PAGE> PAGE 31
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<PAGE> PAGE 32
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<PAGE> PAGE 33
070 A010900 Y
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<PAGE> PAGE 34
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<PAGE> PAGE 35
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<PAGE> PAGE 36
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<PAGE> PAGE 37
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<PAGE> PAGE 38
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<PAGE> PAGE 39
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<PAGE> PAGE 40
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SIGNATURE JENNIFER B. MCHUGH
TITLE ATTORNEY
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PricewaterhouseCoopers LLP
1177 Avenue of the Americas
New York, NY 10036
Report of Independent Accountants
To the Shareholders and Board of Directors of
MainStay Institutional Funds, Inc.
In planning and performing our audit of the financial statements of MainStay
Institutional Funds Inc. (the "Funds") for the year ended December 31, 1998, we
considered their internal controls, 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 controls.
The management of the Funds 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 control, errors or fraud may occur
and 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 error 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
December 31, 1998.
This report is intended solely for the information and use of management and the
Board of Directors of the Funds and the Securities and Exchange Commission.
PricewaterhouseCoopers LLP
New York, New York
February 26, 1999
