<PAGE>
[Eaton Vance Logo] [Statue of Liberty]
Semiannual Report June 30, 2000
EATON VANCE
INSTITUTIONAL
[Monument] SHORT TERM
TREASURY
FUND
[Flag] [75th Anniversary Logo]
<PAGE>
Eaton Vance Institutional Short Term Treasury Fund as of June 30, 2000
INVESTMENT UPDATE
Investment Environment
--------------------------
The Economy
- In response to a strong economy
and signs of rising inflation, the
Federal Reserve Board raised
the Federal Funds rate, a key
[PHOTO] barometer of short-term interest
rates, on six occasions in the past
Michael B. Terry 13 months. The Fed has been
Portfolio Manager especially concerned that rising
labor costs and increased demand,
despite improvements in productivity, could lead to higher inflation.
- There is evidence that the Fed's rate hikes are starting
to have the desired effect of producing a "soft landing"
for the economy. Interest rate-sensitive sectors of the
economy, especially housing and construction, have
slowed significantly. Although still healthy, consumer
spending has cooled off.
- Recent inflation indicators have been favorable. Wage
gains, a source of concern in a tight labor market,
showed little movement in May. Increases in the
Producer Price Index and the Consumer Price Index
have been benign, and the number of manufacturers
experiencing price increases from suppliers dropped
off sharply.
The Market
- Short-term treasury rates rose as the Fed continued to
tighten interest rates (see chart at right). The short end
of the Treasury yield curve (where the Fund invests)
was dominated by the prospects for Fed tightening. At
times when the Fed is expected to raise rates, the
curve can get very steep in anticipation. This was
the case in the first half of 2000, but was less so at
mid-year as the Fed appeared unlikely to move
much further.
The Fund
--------------------------
The Past Six Months
- During the six months ended June 30, 2000,
Eaton Vance Institutional Short-Term Treasury
Fund had a total return of 2.63%.1
- This return resulted from an increase in the Fund's
net asset value to $72.46 per share on June 30, 2000,
from $70.60 per share on December 31, 1999.
- Eaton Vance Institutional Short-Term Treasury
Fund invests only in Treasury obligations with a
remaining maturity of up to 5 years and Treasury-
collateralized repurchase agreements. The Fund
continued to offer both very low credit risk compared
to corporate bond funds and minimal interest rate
sensitivity compared to longer-term fixed-income
mutual funds.
Six-Month Treasury Bill Yield
January 1, 2000 - June 30, 2000*
[CHART]
January 1, 2000 June 30, 2000
*Source: Bloomberg, L.P.
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Mutual fund shares are not insured by the FDIC and are not deposits or other
obligations of, or guaranteed by, any depository institution. Shares are subject
to investment risks, including possible loss of principal invested.
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Fund Information
as of June 30, 2000
Performance(1)
----------------------------------------------
SEC Average Annual Total Returns
----------------------------------------------
One Year 5.00%
Life of Fund+ 4.69%
+Inception Date -- 1/4/99
(1) Returns are historical and are calculated by determining the percentage
change in net asset value with all distributions reinvested. There is
no sales charge.
Past performance is no guarantee of future results. Investment return and
principal value will fluctuate so that shares, when redeemed, may be worth
more or less than their original cost.
2
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EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
PORTFOLIO OF INVESTMENTS (UNAUDITED)
U.S. TREASURY OBLIGATIONS -- 50.3%
<TABLE>
<CAPTION>
PRINCIPAL
AMOUNT
SECURITY (000'S OMITTED) VALUE
<S> <C> <C>
-----------------------------------------------------------------------
U.S. Treasury Bill, 9/7/00 $132,000 $130,584,960
U.S. Treasury Bill, 9/14/00 64,000 63,244,800
U.S. Treasury Bill, 11/2/00 50,000 48,995,000
U.S. Treasury Bill, 11/9/00 73,000 71,434,150
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Total U.S. Treasury Obligations
(identified cost, $314,233,953) $314,258,910
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</TABLE>
REPURCHASE AGREEMENTS -- 49.7%
<TABLE>
<CAPTION>
PRINCIPAL
AMOUNT
SECURITY (000'S OMITTED) VALUE
<S> <C> <C>
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Banc One Capital Markets Repurchase
Agreement, dated 6/30/00, due 7/3/00,
with a maturity value of $155,082,667
and an effective yield of 6.40%,
collateralized by U.S. Treasury
Obligations with rates ranging from
4.625% to 7.75%, with maturity dates
ranging from 7/6/00 to 2/28/03 and with
an aggregate market value of
$156,633,494. $155,000 $155,027,556
Dean Witter Repurchase Agreement, dated
6/30/00, due 7/3/00, with a maturity
value of $155,083,829 and an effective
yield of 6.49%, collateralized by U.S.
Treasury Obligations with rates ranging
from 6.25% to 8.00%, with maturity dates
ranging from 5/15/01 to 2/15/05 and with
an aggregate market value of
$156,092,980. 155,000 155,027,943
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Total Repurchase Agreements
(identified cost $310,055,499) $310,055,499
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Total Investments -- 100.0%
(identified cost $624,289,452) $624,314,409
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Other Assets, Less Liabilities -- 0.0% $ 47,829
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Net Assets -- 100.0% $624,362,238
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</TABLE>
SEE NOTES TO FINANCIAL STATEMENTS
3
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
FINANCIAL STATEMENTS (UNAUDITED)
STATEMENT OF ASSETS AND LIABILITIES
<TABLE>
<CAPTION>
AS OF JUNE 30, 2000
<S> <C>
Assets
------------------------------------------------------
Investments, at value
(identified cost, $624,289,452) $624,314,409
Cash 47,829
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TOTAL ASSETS $624,362,238
------------------------------------------------------
NET ASSETS FOR 8,616,906 SHARES OF
BENEFICIAL INTEREST OUTSTANDING $624,362,238
------------------------------------------------------
Sources of Net Assets
------------------------------------------------------
Paid-in capital $614,647,570
Accumulated undistributed net realized
gain (computed on the basis of
identified cost) 168,378
Accumulated undistributed net
investment income 9,521,333
Net unrealized appreciation (computed on
the basis of identified cost) 24,957
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TOTAL $624,362,238
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Net Asset Value, Offering Price
and Redemption Price Per Share
------------------------------------------------------
($624,362,238 DIVIDED BY 8,616,906
SHARES OF BENEFICIAL INTEREST
OUTSTANDING) $ 72.46
------------------------------------------------------
</TABLE>
STATEMENT OF OPERATIONS
<TABLE>
<CAPTION>
FOR THE SIX MONTHS ENDED
JUNE 30, 2000
<S> <C>
Investment Income
-----------------------------------------------------
Interest $10,588,238
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TOTAL INVESTMENT INCOME $10,588,238
-----------------------------------------------------
Expenses
-----------------------------------------------------
Investment adviser fee $ 623,726
Service fees 443,179
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TOTAL EXPENSES $ 1,066,905
-----------------------------------------------------
NET INVESTMENT INCOME $ 9,521,333
-----------------------------------------------------
Realized and Unrealized Gain (Loss)
-----------------------------------------------------
Net realized gain (loss) --
Investment transactions (identified
cost basis) $ 168,378
-----------------------------------------------------
NET REALIZED GAIN $ 168,378
-----------------------------------------------------
Change in unrealized
appreciation (depreciation) --
Investments (identified cost basis) $ 24,884
-----------------------------------------------------
NET CHANGE IN UNREALIZED APPRECIATION
(DEPRECIATION) $ 24,884
-----------------------------------------------------
NET REALIZED AND UNREALIZED GAIN $ 193,262
-----------------------------------------------------
NET INCREASE IN NET ASSETS FROM
OPERATIONS $ 9,714,595
-----------------------------------------------------
</TABLE>
SEE NOTES TO FINANCIAL STATEMENTS
4
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
FINANCIAL STATEMENTS CONT'D
STATEMENTS OF CHANGES IN NET ASSETS
<TABLE>
<CAPTION>
SIX MONTHS ENDED
INCREASE (DECREASE) JUNE 30, 2000 PERIOD ENDED
IN NET ASSETS (UNAUDITED) DECEMBER 31, 1999(1)
<S> <C> <C>
--------------------------------------------------------------------------------
From operations --
Net investment income $ 9,521,333 $ 21,440,419
Net realized gain 168,378 13,346
Net change in unrealized
appreciation (depreciation) 24,884 73
--------------------------------------------------------------------------------
NET INCREASE IN NET ASSETS
FROM OPERATIONS $ 9,714,595 $ 21,453,838
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Distributions to shareholders --
From net investment income $ -- $ (33,199)
--------------------------------------------------------------------------------
TOTAL DISTRIBUTIONS TO SHAREHOLDERS $ -- $ (33,199)
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Transactions in shares of beneficial interest --
Proceeds from sale of shares $ 855,488,542 $ 720,116,543
Net asset value of shares issued to
shareholders in payment of
distributions declared -- 33,199
Cost of shares redeemed (241,842,684) (740,568,666)
--------------------------------------------------------------------------------
NET INCREASE (DECREASE) IN NET ASSETS
FROM FUND SHARE TRANSACTIONS $ 613,645,858 $ (20,418,924)
--------------------------------------------------------------------------------
NET INCREASE IN NET ASSETS $ 623,360,453 $ 1,001,715
--------------------------------------------------------------------------------
Net Assets
--------------------------------------------------------------------------------
At beginning of period $ 1,001,785 $ 70
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AT END OF PERIOD $ 624,362,238 $ 1,001,785
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Accumulated undistributed
net investment income
included in net assets
--------------------------------------------------------------------------------
AT END OF PERIOD $ 9,521,333 $ --
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</TABLE>
(1) For the period from the start of business, January 4, 1999, to
December 31, 1999.
SEE NOTES TO FINANCIAL STATEMENTS
5
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
FINANCIAL STATEMENTS CONT'D
FINANCIAL HIGHLIGHTS
<TABLE>
<CAPTION>
SIX MONTHS ENDED
JUNE 30, 2000 YEAR ENDED
(UNAUDITED)(1) DECEMBER 31, 1999(2)(3)
<S> <C> <C>
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Net asset value -- Beginning of period $ 70.600 $70.000
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Income (loss) from operations
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Net investment income $ 1.820 $ 3.015
Net realized and unrealized gain 0.040 0.005
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TOTAL INCOME FROM OPERATIONS $ 1.860 $ 3.020
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Less distributions
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From net investment income -- $(2.420)
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TOTAL DISTRIBUTIONS -- $(2.420)
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NET ASSET VALUE -- END OF PERIOD $ 72.460 $70.600
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TOTAL RETURN(4) 2.63% 4.32%
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Ratios/Supplemental Data
---------------------------------------------------------------------------------------
Net assets, end of period (000's
omitted) $624,362 $ 1,002
Expenses 0.60%(5) 0.60%(5)
Net investment income 5.32%(5) 4.23%(5)
Portfolio Turnover 6% 11%
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</TABLE>
(1) Net investment income per share was computed as its proportionate share
of the net increase in net assets from operations per share.
(2) Net investment income per share was computed using average shares
outstanding.
(3) For the period from the start of business, January 4, 1999, to
December 31, 1999.
(4) Total return is calculated assuming a purchase at the net asset value on
the first day and a sale at the net asset value on the last day of each
period reported. Dividends and distributions, if any, are assumed
reinvested at the net asset value on the reinvestment date. Total return
is not computed on an annualized basis.
(5) Annualized.
SEE NOTES TO FINANCIAL STATEMENTS
6
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
1 Significant Accounting Policies
-------------------------------------------
Eaton Vance Institutional Short Term Treasury Fund (the Fund) is a
non-diversified series of Eaton Vance Special Investment Trust (the Trust).
The Trust is an entity of the type commonly known as a Massachusetts business
trust and is registered under the Investment Company Act of 1940, as amended,
as an open-end management investment company. The Fund's investment objective
is to seek current income and liquidity by investing exclusively in U.S.
Treasury obligations (bills, notes and bonds) with a remaining maturity of up
to five years and repurchase agreements collateralized exclusively by U.S.
Treasury obligations. The following is a summary of significant accounting
policies consistently followed by the Fund in the preparation of its
financial statements. The policies are in conformity with generally accepted
accounting principles.
A Investment Valuations -- Debt securities, including listed securities and
securities for which price quotations are available, will normally be valued
on the basis of market valuations furnished by a pricing service. Short-term
obligations and money market securities maturing in 60 days or less are
valued at amortized cost, which approximates value. Investments for which
valuations or market quotations are unavailable are valued at fair value
using methods determined in good faith by or at the direction of the
Trustees.
B Income -- Interest income is determined on the basis of interest accrued,
adjusted for amortization of discount when required for federal income tax
purposes.
C Federal Taxes -- The Fund's policy is to comply with the provisions of the
Internal Revenue Code applicable to regulated investment companies and to
distribute to shareholders all of its taxable income, including any net
realized gain on investments. Accordingly, no provision for federal income or
excise tax is necessary.
D Distributions to Shareholders -- It is the present policy of the Fund to pay
dividends and capital gains annually, normally in December. The Fund intends
on its tax return to treat as a distribution of investment company taxable
income and net capital gain the portion of redemption proceeds paid to
redeeming shareholders that represents the redeeming shareholders' portion of
the Fund's undistributed investment company taxable income and net capital
gain. This practice, which involves the use of equalization accounting, will
have the effect of reducing the amount of income and gains that the Fund is
required to distribute as dividends to shareholders in order for the Fund to
avoid federal income tax and excise tax. This practice may also reduce the
amount of distributions required to be made to nonredeeming shareholders and
defer the recognition of taxable income by shareholders. However, since the
amount of any undistributed income will be reflected in the value of the
Fund's shares, the total return on a shareholder's investment will not be
reduced as a result of the Fund's distribution policy.
Generally accepted accounting principles require that only distributions in
excess of tax basis earnings and profits be reported in the financial
statements as a return of capital. Differences in the recognition or
classification of income between the financial statements and tax earnings
and profits which result in temporary over distributions for financial
statement purposes are classified as distributions in excess of net
investment income or accumulated net realized gains. Permanent differences
between book and tax accounting relating to distributions are reclassified to
paid-in capital.
E Repurchase Agreements -- The Fund may enter into repurchase agreements
collateralized exclusively by US Treasury obligations with banks and
broker-dealers determined to be creditworthy by the Investment Adviser. Under
a repurchase agreement, the Fund buys a security at one price and
simultaneously promises to sell that same security back to the seller at a
higher price for settlement at a later date. The Fund's repurchase agreements
will provide that the value of the collateral underlying the repurchase
agreement will always be at least equal to the repurchase price, including
any interest earned on the repurchase agreement, and will be marked to market
daily. The repurchase date is usually overnight, but may be within seven days
of the original purchase date. In the event of bankruptcy of the counterparty
or a third party custodian, the Fund might experience delays in recovering
its cash or experience a loss.
F Other -- Investment transactions are accounted for on a trade date basis.
Dividends to shareholders are recorded on the ex-dividend date.
G Use of Estimates -- The preparation of financial statements in conformity
with generally accepted accounting principles requires management to make
estimates and assumptions that affect the reported amounts of assets and
liabilities at the date of the financial statements and the reported amounts
of income and expense during the reporting period. Actual results could
differ from those estimates.
7
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
NOTES TO FINANCIAL STATEMENTS (UNAUDITED) CONT'D
H Interim Financial Statements -- The interim financial statements relating to
June 30, 2000 and for the six months then ended have not been audited by
independent certified public accountants, but in the opinion of the Fund's
management reflect all adjustments, consisting only of normal recurring
adjustments, necessary for the fair presentation of the financial statements.
2 Shares of Beneficial Interest
-------------------------------------------
The Declaration of Trust permits the Trustees to issue an unlimited number of
full and fractional shares of beneficial interest (without par value).
Transactions in Fund shares were as follows:
<TABLE>
<CAPTION>
SIX MONTHS ENDED
JUNE 30, 2000 YEAR ENDED
(UNAUDITED) DECEMBER 31, 1999(1)
<S> <C> <C>
------------------------------------------------------------------------------------
Sales 11,974,003 10,231,236
Issued to shareholders electing to
receive payments of distributions in
Fund shares -- 470
Redemptions (3,371,286) (10,217,518)
------------------------------------------------------------------------------------
NET INCREASE 8,602,717 14,188
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</TABLE>
(1) For the period from the start of business, January 4, 1999, to
December 31, 1999.
3 Purchases and Sales of Investments
-------------------------------------------
Purchases and sales (including maturities) of U.S. Government Securities
aggregated $1,448,349,756 and $1,140,492,985, respectively.
4 Management Fee and Other Transactions with Affiliates
-------------------------------------------
The management fee is earned by Eaton Vance Management (EVM) as compensation
for management services rendered to the Fund. The fee is at an annual rate of
0.35% of the average daily net assets of the Fund. Eaton Vance also provides
administrative services and pays all ordinary operating expenses of the Fund
(except service and management fees). For the period ended June 30, 2000, the
fee was equivalent to 0.35% of the Fund's average net assets and amounted to
$623,726. Except as to Trustees of the Fund who are not members of EVM's
organization, officers and Trustees receive remuneration for their services
to the Fund out of such investment adviser fee. Certain officers and Trustees
of the Fund are officers of the above organizations. Trustees of the Fund
that are not affiliated with the Investment Adviser may elect to defer
receipt of all or a percentage of their annual fees in accordance with the
terms of the Trustees Deferred Compensation Plan. For the period ended
June 30, 2000, no significant amounts have been deferred.
5 Service Plan
-------------------------------------------
The Fund has adopted a service plan. Fund assets bear a service fee for
personal and/or account services paid to the Principal Underwriter, Eaton
Vance Distributors, Inc. (EVD), a subsidiary of EVM, in an amount not
exceeding 0.25% of average daily net assets. EVD may pay up to the entire
amount of the service fee to investment dealers and their employees, or to
EVD employees for providing services to the Fund or its shareholders. Service
fee payments from EVD to investment dealers and others will be made on new
accounts only if EVD has previously authorized in writing such payments for
identified accounts. For the period ended June 30, 2000, the Fund paid
$443,179 in service fees to EVD, and EVD in turn paid a substantial portion
of this amount to investment dealers.
6 Line of Credit
-------------------------------------------
The Fund participates with other portfolios and funds managed by EVM and its
affiliates in a $150 million unsecured line of credit agreement with a group
of banks. Borrowings will be made by the Fund solely to facilitate the
handling of unusual and/or unanticipated short-term cash requirements.
Interest is charged to each portfolio or fund based on its borrowing at an
amount above the Eurodollar rate or federal funds rate. In addition, a fee
computed at an annual rate of 0.10% on the daily unused portion of the
facility is allocated among the participating portfolios and funds at the end
of each quarter. The Fund did not have any significant borrowings or
allocated fees during the period ended June 30, 2000.
7 Federal Income Tax Basis of Investments
-------------------------------------------
The cost and unrealized appreciation (depreciation) in value of the
investment securities at June 30, 2000, as computed on a federal income tax
basis, were as follows:
<TABLE>
<S> <C>
AGGREGATE COST $624,289,452
------------------------------------------------------
Gross unrealized appreciation $ 26,337
Gross unrealized depreciation (1,380)
------------------------------------------------------
NET UNREALIZED APPRECIATION $ 24,957
------------------------------------------------------
</TABLE>
8
<PAGE>
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND AS OF JUNE 30, 2000
INVESTMENT MANAGEMENT
Officers
James B. Hawkes
President and Trustee
Edward E. Smiley, Jr.
Vice President
Michael B. Terry
Vice President and
Portfolio Manager
James L. O'Connor
Treasurer
Alan R. Dynner
Secretary
Trustees
Jessica M. Bibliowicz
President and Chief Executive Officer,
National Financial Partners
Donald R. Dwight
President, Dwight Partners, Inc.
Samuel L. Hayes, III
Jacob H. Schiff Professor of Investment
Banking Emeritus, Harvard University Graduate
School of Business Administration
Norton H. Reamer
Chairman of the Board,
United Asset Management Corporation
Lynn A. Stout
Professor of Law,
Georgetown University Law Center
Jack L. Treynor
Investment Adviser and Consultant
9
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THIS PAGE INTENTIONALLY LEFT BLANK
<PAGE>
INVESTMENT ADVISER
EATON VANCE MANAGEMENT
The Eaton Vance Building
255 State Street
Boston, MA 02109
PRINCIPAL UNDERWRITER
EATON VANCE DISTRIBUTORS, INC.
The Eaton Vance Buildings
255 State Street
Boston, MA 02109
(617) 482-8260
CUSTODIAN
INVESTORS BANK & TRUST COMPANY
200 Clarendon Street
Boston, MA 02116
TRANSFER AGENT
PFPC, INC.
Attn: Eaton Vance Funds
P.O. Box 9653
Providence, RI 02904-9653
(800) 262-1122
EATON VANCE INSTITUTIONAL SHORT TERM TREASURY FUND
THE EATON VANCE BUILDING
255 STATE STREET
BOSTON, MA 02109
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This report must be preceded or accompanied by a current prospectus which
contains more complete information on the Fund, including its distribution plan,
sales charges and expenses. Please read the prospectus carefully before you
invest or send money.
--------------------------------------------------------------------------------
163-8/00 TYSRC
