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October 1, 2001*

Federal Reserve Bank of Cleveland

How Well Does the Federal Funds Futures
Rate Predict the Future Federal Funds Rate?
by Ed Nosal

I

n order to meet their reserve requirements, banks often borrow money for
short periods (typically overnight) to
make up transitory cash shortfalls. Usually, they borrow in the federal funds
market from other banks that have excess
reserves on hand. The interest rate that is
paid on these borrowed reserves is called
the federal funds rate. When the Federal
Reserve announces a change in interest
rates, this is the rate that it attempts to
change. The Fed cannot perfectly control
the rate because it is determined by supply of and demand for reserves. What the
Fed does instead is set a target rate and
then buy or sell government securities
(open market operations) so that the
actual federal funds rate is, on average,
equal to the target.
The Fed’s target interest rate on federal
funds is followed closely, and expected
changes in the future rate can affect the
behavior of individuals and institutions.
For example, if banks expect the fed
funds rate to increase, they will hold, on
average, less reserves. Businesses other
than banks may be concerned about rate
changes, too, since changes in the fed
funds rate may ultimately affect the
interest rates they care about. Business
and investment decisions depend, in part,
on what companies expect these rates
will be in the future. For example, suppose a company must decide today
whether to undertake a project in the
future. Its decision will be affected by

ISSN 0428-1276
*Printed December 2001

its perception of future borrowing costs.
If future borrowing costs are related to
the future fed funds rate, then the company may choose not to undertake a project that is profitable at current borrowing
rates if it expects the fed funds rate to be
higher in the future. Alternatively, it may
choose to undertake a project in the
future that is unprofitable at current borrowing rates if it expects the fed funds
rate to be lower in the future.
Movements in the fed funds rate expose
banks and other businesses to risk. In the
case of banks, rate changes directly affect
their cost of overnight borrowing. For
others, fed funds rate changes may mean
interest rates on business loans or investments will change, too. Banks can hedge
against fed funds interest rate risk by participating in the fed funds futures market.
Since other businesses often are not
directly affected by the fed funds rate,
this futures market may not be an ideal
hedging vehicle for them. However, the
rate at which fed funds futures are selling
may provide information that can help
determine what the future rate might be
on instruments that do concern them.
Businesses use the rates on fed funds
futures to forecast future fed funds and
other interest rates. But how closely is
the futures rate related to what the fed
funds rate turns out to be? We have reason to believe that the futures rate on
average overpredicts the fed funds rate,
and, over different phases of the business
cycle, may systematically over- or
underpredict the eventual fed funds
rates.

Contrary to popular belief, federal
funds futures rates do not tell us precisely where the market thinks federal funds rates will be in the future.
On average, futures rates overpredict
future fed funds rates, and, depending on whether fed funds rates are
falling or rising, the futures rate may
consistently overestimate or underestimate the future fed funds rates.
To obtain a reliable estimate of the
future fed funds rate, one must adjust
the fed funds futures rate appropriately to account for the bias and past
movements of the fed funds rate.

■

The Federal Funds Futures
Contract

The federal funds futures contract is an
interest rate futures contract that is based
on the average federal funds rate over a
particular calendar month. A contract
can be written for any month up to 24
months in the future. The standard contract has a notional value of $5 million,
and contracts are settled on a daily basis.
Conceptually, it is best to think of a
futures contract as specifying that a certain good or asset is to be delivered at
some future date at a pre-set price, the
futures price. A fed funds futures contract can then be interpreted as specifying that one bank delivers an overnight
loan to another bank at some future date
at a predetermined interest rate, the federal funds futures rate. By entering into

a fed funds futures contract a bank is
able to essentially “lock in” a rate for
future borrowing or lending.1

■

The Fed Funds Futures Rate
and the Expected Future Fed
Funds Rate

It is quite sensible to conjecture that the
expected future fed funds rate is somehow related to the fed funds futures rate.
(If it were not, the fed funds futures
market would not be efficient.) But
should one simply interpret the fed
funds futures rate as the fed funds rate
that “the market” actually expects to
prevail in the future?
In theory, there are reasons to believe
that the fed funds futures rate will typically overestimate the future fed funds
rate. To understand this, note that, while
futures contracts can help minimize risk,
they are nonetheless financial instruments that promise to deliver (other)
financial instruments that do carry some
risk. Incorporated into the futures rate is
a premium for compensating buyers for
this risk. The following example should
make this idea clear.
Consider a futures contract on a pure
discount bond. A pure discount bond
provides its holder with a single payment upon maturity. I use the example
of a pure discount bond because the
federal funds rate applies to a financial
instrument—an overnight loan—that is,
in fact, a pure discount bond with maturity of one day. Suppose that someone
enters into a futures contract that
requires him to deliver a pure discount
bond that matures in 90 days, where
delivery will occur 30 days from now.
At maturity the bond will pay $100.
He can ensure he has something to
deliver by purchasing a 120-day pure
discount bond today and holding it for
30 days: After 30 days the 120-day pure
discount bond becomes a 90-day pure
discount bond.
As we shall see, this buy-and-hold strategy will tell us what the futures price
should be. In particular, if the 120-day
pure discount bond costs $95 and the
interest cost associated with financing a
$95 loan for 30 days is $1, then the total
cost associated with the buy-and-hold
strategy is $96. (Note that the financing
cost is relevant even if one has the $95

in hand because, by purchasing the
120-day pure discount bond, one foregoes the $1 that could have been earned.)
The buy-and-hold strategy ensures that a
90-day pure discount bond will be delivered in 30 days. Since the cost of the
buy-and-hold strategy is $96, no one
would be willing to pay more than $96
for a 90-day pure discount bond 30 days
from now. Hence, the futures price—the
price that someone pays for delivery of
a 90-day pure discount bond delivered
30 days from now—must be $96.
Continuing with the example, one can
interpret the futures contract as providing a return of $1 for sure to anyone who
delivers a futures contract using the buyand-hold strategy. The actual return
associated with a 120-day pure discount
bond 30 days from now, however, is
uncertain: The price may turn out to be
$96, but it could also be $94 or $98.
Given that people generally do not like
risk, they will be willing to purchase the
120-day pure discount bond today (without any offsetting futures contract) only
if the price of the bond is expected to
exceed $96 in 30 days. That is, an individual must be compensated for the
“risk” that is inherent in the bond before
its maturity date, implying that the
expected 30-day return must be greater
than the $1 that can be earned for certain. As a result, the expected price of the
120-day pure discount bond 30 days
from now—which is simply the current
price plus its expected 30-day return—
must exceed $96. Suppose that the
expected price of the 120-day pure discount bond 30 days from now is $97,
implying an expected 30-day return of
$2. Therefore, the futures price, $96,
underestimates the price that is expected
to prevail in the future, $97.
Because there is a simple inverse relationship between bond prices and
returns, the futures rate overestimates
the rate that is expected to prevail in the
future. Note that the rate we refer to is
the rate of return associated with a
90-day pure discount bond that pays
$100 at maturity. If one purchases the
90-day pure discount bond for $96,
which one is able to do via a futures
contract, then the rate of return on the
90-day pure discount bonds is 4.2 percent over 90 days (the $4 one earns is
4.2 percent of the $96 invested). On the

other hand, if one purchases the 90-day
pure discount bond on the open market
for $97, the expected return is 3.1 percent over 90 days ($3 is 3.1 percent of
$97). Hence, the futures rate of return
of 4.2 percent exceeds the expected rate
of return of 3.1 percent.
Theory suggests that the fed funds
futures rate overpredicts the expected
future fed funds rate. Is this consistent
with the data? Before we can answer
this question, we must grapple with an
empirical issue: We must decide how
we’ll measure what the market expects
the future fed funds rate to be. For our
purpose, we will assume that futures
rates do represent the market’s expected
future fed funds rate. The following
approach is taken. We’ll compare the
average difference between futures
rates on contracts that mature in a given
month and the average fed funds rate
that prevailed during that month.
For example, consider a four-month fed
funds futures contract (delivery of the
funds will occur four months from when
the contract is signed). If the rate on this
contract is 3.4 percent on December 31,
1993, it means, loosely speaking, that a
bank entering into the contract must
either accept or make delivery, depending on whether it bought or sold the
contract, of an overnight loan on
April 30, 1994, at an interest rate of
3.4 percent. The fed funds rate for
April 1994 turns out to be 3.548 percent.
So, in this instance, the difference
between the fed funds futures rate and
the fed funds rate is –0.148. We apply
this procedure for all months between
April 1989 and October 2001. This
enables us to calculate the average
difference between the fed funds futures
rate and the actual fed funds rate.
Over the period April 1989 to October
2001, the fed funds futures rate
exceeded the future fed funds rate by
0.187 percent on average, and this
difference is statistically different from
zero. Hence, on average, the data are
consistent with the theory; the futures
rate exceeds the expected rate. This
suggests that if someone wants to make
an educated guess as to what the fed
funds rate will be in four months, he
should subtract 0.187 percent from the
current four-month fed funds futures
rate. Subtracting 0.187 percent removes

FIGURE 1 THE FED FUNDS RATE AND THE ADJUSTED FED FUNDS FUTURES RATE
12

10

8
Adjusted futures rate a
6

4
Average effective fed funds rate b
2

0
1989

1991

1993

1995

1997

1999

2001

a. The adjusted rate is the monthly average of the daily fed funds futures rate minus 0.187, the average amount by which the futures rate overpredicted
the fed funds rate from April 1989 to October 2001.
b. Daily fed funds rates were averaged for each month.
SOURCES: Board of Governors of the Federal Reserve System, Federal Reserve Statistical Releases, “Selected Interest Rates,” H.15; Chicago Board of
Trade; and Bloomberg Financial Information Services.

the bias contained in the fed funds
futures rate. If one plots the “adjusted”
fed funds futures rate—the fed funds
futures rate minus 0.187 percent—and
the fed funds rate over time, one might
expect that the two series should closely
resemble one another. After all, when
the bias is removed, the average
“adjusted” fed funds rate equals the
actual average funds rate.
The two series are displayed in figure 1
and, perhaps surprisingly, they do not
closely resemble one another. The figure
has two rather striking features. First,
when the fed funds rate is falling (for
example, 1991–1993, and from 2001
onward), the futures rate tends to overestimate the fed funds rate, and when
the fed funds rate is rising (for example,
1994–1995 and 1999–mid 2000) the
futures rate tends to underestimate the
target rate.
These systematic biases do not necessarily reflect some inefficiency in the
futures market. To see this, suppose that
the Fed has recently cut the target fed
funds rate after a period of unchanging
targets, and you have to forecast the fed
funds rate four months into the future.
Given the information that you currently

possess, it is unlikely that you will be
able to conclude for certain that the Fed
will either initiate another cut
or keep the fed funds rate unchanged in
the future. Both of these events are possible. (Since the Fed just cut the fed
funds target rate after a period of
unchanging target rates, you are pretty
certain that the Fed will not increase the
target rate in the near future.) So, when
you form your forecast of the future fed
funds rate, it will be a weighted average
of the current fed funds rate (that is, the
Fed does not cut the target in the future)
and a lower fed funds rate (the Fed does
cut the target in the future). If the Fed,
in fact, ends up cutting the fed funds
rate in the future, your forecasted fed
funds rate will be higher than the actual
fed funds rate. To the extent that the fed
funds future market embodies these
expectations, the fed funds futures rate
may systematically overestimate the
future fed funds rates when fed fund
rates are falling and, by symmetry,
underestimate the future fed funds rate
when fed funds rates are rising.

■ Summary
What do fed funds futures rates tell us
about future fed funds rates? The
futures rate does not tell us where the

market thinks rates will be in the future.
Fed funds futures rates, on average,
overpredict future fed funds rates. Even
if this bias is removed, which implies
that, on average, fed funds futures rates
are equal to future fed funds rates, the
fed funds futures rate does not provide
one with a reliable estimate of future
fed funds rates at a particular point in
time: Depending on the future course of
the fed funds rates, the futures rate may
either consistently overestimate or
underestimate future fed funds rates.
This is not to say that the fed funds
futures rate does not contain any information about the market’s expectation
of the future course of policy. In fact, it
does contain a great amount of information. However, in order to obtain a
reliable estimate of the future fed funds
rate, one must make appropriate adjustments to the fed funds futures rate to
take account of the biases and past
movements of the fed funds rate.

■ Footnotes
1. Of course, in practice the asset that
underlies a futures contract is not
delivered. Instead, contracts are settled
in cash.

Ed Nosal is an economic advisor at the
Federal Reserve Bank of Cleveland.
The views expressed here are those of the
author and not necessarily those of the Federal
Reserve Bank of Cleveland, the Board of
Governors of the Federal Reserve System, or
its staff.
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