MONETARY POLICY REPORT: JULY 2019 37
Monetary Policy Rules and Their Interactions with the Economy
Economists have analyzed many monetary policy
rules, including the well-known Taylor (1993) rule.
Other rules include the “balanced approach” rule, the
“adjusted Taylor (1993)” rule, the “price level” rule, and
the “rst difference” rule (gure A).
3
These policy rules
embody the three key principles of good monetary
policy and take into account estimates of how far the
economy is from the Federal Reserve’s dual-mandate
goals of maximum employment and price stability. Four
of the ve rules include the difference between the rate
of unemployment that is sustainable in the longer run
and the current unemployment rate (the unemployment
rate gap); the rst-difference rule includes the change
in the unemployment gap rather than its level.
4
In
(continued on next page)
Monetary policy rules are mathematical formulas
that relate a policy interest rate, such as the federal
funds rate, to a small number of other economic
variables—typically including the deviation of ination
from its target value and a measure of resource slack in
the economy. The prescriptions for the policy interest
rate from these rules can provide helpful guidance for
the Federal Open Market Committee (FOMC). This
discussion presents ve policy rules—illustrative of the
many rules that have received attention in the research
literature—and provides examples of two ways to
compute historical prescriptions of policy rules. The
two ways differ in terms of whether the implications
of the rule prescriptions feed through to the
macroeconomy and potentially back to the policy rule
prescriptions themselves. The presentation highlights
the uses and limitations of each way for informing the
FOMC’s systematic conduct of monetary policy.
Historical Prescriptions of Policy Rules
The effectiveness of monetary policy is enhanced
when it is well understood by the public.
1
In simple
models of the economy, good economic performance
can be achieved by following a monetary policy rule
that fosters public understanding and that incorporates
key principles of good monetary policy.
2
One such
principle is that monetary policy should respond in a
predictable way to changes in economic conditions.
A second principle is that monetary policy should be
accommodative when ination is below policymakers’
longer-run ination objective and employment is below
its maximum sustainable level; conversely, monetary
policy should be restrictive when the opposite holds. A
third principle is that, to stabilize ination, the policy
rate should be adjusted over time by more than one-for-
one in response to persistent increases or decreases in
ination.
1. For a discussion of how the public’s understanding of
monetary policy matters for the effectiveness of monetary
policy, see Janet L. Yellen (2012), “Revolution and Evolution
in Central Bank Communications,” speech delivered at the
Haas School of Business, University of California at Berkeley,
Berkeley, Calif., November13, https://www.federalreserve.gov/
newsevents/speech/yellen20121113a.htm.
2. For a discussion regarding principles for the conduct
of monetary policy, see Board of Governors of the Federal
Reserve System (2018), “Monetary Policy Principles and
Practice,” Board of Governors, https://www.federalreserve.gov/
monetarypolicy/monetary-policy-principles-and-practice.htm.
3. The Taylor (1993) rule was suggested in John B. Taylor
(1993), “Discretion versus Policy Rules in Practice,” Carnegie-
Rochester Conference Series on Public Policy, vol. 39
(December), pp. 195–214. The balanced-approach rule was
analyzed in John B. Taylor (1999), “A Historical Analysis of
Monetary Policy Rules,” in John B. Taylor, ed., Monetary Policy
Rules (Chicago: University of Chicago Press), pp. 319–41. The
adjusted Taylor (1993) rule was studied in David Reifschneider
and John C. Williams (2000), “Three Lessons for Monetary
Policy in a Low-Ination Era,” Journal of Money, Credit and
Banking, vol. 32 (November), pp. 936–66. A price-level rule
was discussed in Robert E. Hall (1984), “Monetary Strategy
with an Elastic Price Standard,” in Price Stability and Public
Policy, proceedings of a symposium sponsored by the Federal
Reserve Bank of Kansas City, held in Jackson Hole, Wyo.,
August2–3 (Kansas City: Federal Reserve Bank of Kansas
City), pp. 137–59, https://www.kansascityfed.org/publicat/
sympos/1984/s84.pdf. Finally, the rst-difference rule is
based on a rule suggested by Athanasios Orphanides (2003),
“Historical Monetary Policy Analysis and the Taylor Rule,”
Journal of Monetary Economics, vol. 50 (July), pp. 983–1022.
A comprehensive review of policy rules is in John B. Taylor
and John C. Williams (2011), “Simple and Robust Rules for
Monetary Policy,” in Benjamin M. Friedman and Michael
Woodford, eds., Handbook of Monetary Economics, vol. 3B
(Amsterdam: North-Holland), pp. 829–59. The same volume
of the Handbook of Monetary Economics also discusses
approaches other than policy rules for deriving policy rate
prescriptions.
4. The Taylor (1993) rule represented slack in resource
utilization using an output gap (the difference between the
current level of real gross domestic product (GDP) and the
level that GDP would be if the economy were operating at
maximum employment, measured in percent of the latter.
The rules in gure A represent slack in resource utilization
using the unemployment gap instead, because that gap better
captures the FOMC’s statutory goal to promote maximum
employment. However, movements in these alternative
measures of resource utilization are highly correlated. For
more information, see the note below gure A.