speeches · April 10, 2007
Regional President Speech
Jeffrey M. Lacker · President
“Inflation and Unemployment” 1
Charlotte Economics Club
Charlotte NC
April 11, 2007
Jeffrey M. Lacker
President, Federal Reserve Bank of Richmond
Let me begin by telling you about some recent experiences. I had the opportunity earlier
this year to guest-teach a couple of business school economics classes. I opened my
discussions with a pair of questions, asking students to put themselves in the place of a
monetary policymaker choosing a target for the federal funds rate. First I gave them a set
of hypothetical facts about the state of the economy: a slowdown in housing in the wake
of multi-year housing boom; rising mortgage default rates; preliminary indicators of a
slowing in business investment. And then I asked them: “What are you going to do?”
The students dutifully responded that this situation could call for a reduction in the funds
rate. They’d obviously been doing their homework.
Next, I gave them a set of hypothetical facts about inflation: core PCE inflation, on a
year-over-year basis, has been above 2 percent for nearly three straight years; after some
signs of moderation, recent months’ inflation numbers have moved higher; energy prices
have been fluctuating around historically elevated levels and labor compensation is rising
after a relatively flat period. Same question: “What are you going to do?” Once again,
their response came right out of the textbook: an increase in the funds rate is needed to
counter rising inflation, other things equal.
The trick of course is that both sets of hypothetical facts are drawn from the same period
– basically right now. My objective was to underscore the fact that sometimes monetary
policy decisions are not obvious, and that figuring out the appropriate policy action
requires as complete a picture as possible of the state of the economy. Interpreting that
picture and drawing policy conclusions from it can be a challenging task.
The situation I presented to the students represents a policymaking dilemma.
The actions needed to bring down inflation could work against our desire to see the real
outlook solidify. The facts would appear to present the policymaker with a tradeoff. You
can address one – inflation or real growth – but that puts the other at risk. The obvious
approach might be to decide how much “weight” one puts on each – low inflation and
low unemployment – and then try to conduct policy so as to minimize the weighted
average of the two. There is a superficial attraction to this popular view of the situation as
a simple tradeoff. But that characterization is also, I think, an extreme oversimplification and can be highly misleading. I’d like to devote my remarks today to the
relationship between inflation and the real side of the economy and to what I think that
relationship implies for policymaking. As always, the views expressed are my own, and
not necessarily the same as others in the Federal Reserve.
The relationship between inflation and the real economy can be described in terms of a
number of alternative measures of real activity. Perhaps the most popular is the
unemployment rate, because it captures the extent to which the expansion in employment
generated by growth in real output is rapid enough to absorb additions to the labor force.
As an indicator of the economy’s use of its resources, the unemployment rate is
commonly used as rough measure of the extent to which real activity is giving rise to
“inflation pressures,” but I will have much more to say about this later on.
Unemployment and inflation have, together, been at the center of macroeconomics for at
least as long as there has been a field called macroeconomics. The relationship between
these two variables is usually summarized by what’s called the Phillips curve, named for
A. W. Phillips, the economist who in 1957 documented an inverse relationship between
unemployment and wage inflation in nearly 100 years of data for the United Kingdom. 2
But the notion that rising inflation might at times be associated with rising real growth
and falling unemployment had been recognized and discussed by early economists, a fact
that has been emphasized by many scholars, including Robert Lucas in his Nobel lecture
and by my long-time Richmond Fed colleague, Thomas Humphrey, who retired in 2005. 3
Since Phillips’ original paper, his curve has played a critical role in the evolution of
thinking about macroeconomics and monetary policy. It captures the notable correlations
between inflation and unemployment, although those correlations vary over time in
important ways. But more importantly, it embodies compactly a theoretical understanding
of the interplay between inflation and real economic forces. Because of its importance,
and because the modern version of the Phillips curve is in some respects starkly different
from the early edition, I think it will be worthwhile to briefly review some of the Phillips
curve’s history, before examining the role it plays today in thinking about monetary
policy.
A.W. Phillips’ curve
The Phillips curve began as an atheoretical relationship drawn to fit the data. The form
with which people are most familiar – linking unemployment to price inflation – was first
set down in 1960 by Paul Samuelson and Robert Solow for U.S. data. 4 Following
Samuelson and Solow, the Phillips curve was interpreted as describing a set of choices
available to society each time period. According to this view, if the data suggested that
price stability tended to coexist, on average, with 5 percent unemployment, we would
have to live with higher inflation to enjoy unemployment persistently lower than 5
percent. This thinking led to descriptions of policy as either stimulating real activity at
the cost of rising inflation, or fighting inflation by restraining the real economy. This
understanding of the Phillips curve seems to have contributed to a political sentiment
that, at least when inflation was relatively low, the costs of a little more inflation were
worth the return in reduced unemployment.
But an alternative understanding of the Phillips curve was emerging in the 1960s. Milton
Friedman and Edmund Phelps, separately, focused on the role of expectations in the
2
relationship between inflation and unemployment. 5 Specifically, they argued that while
inflationary policy actions that were not anticipated by the public could have a temporary
stimulative effect on the economy, fully anticipated inflation would not affect real
activity. Similarly, surprise disinflation could have a temporary contractionary effect but
fully anticipated disinflation would not. This meant that the observed correlation in the
data between inflation and unemployment must have come largely from episodes in
which changes in the inflation rate were not expected by the public.
According to the expectation-augmented Phillips curve developed by Friedman and
Phelps, changes in inflation, and by implication monetary policy, could not have
persistent, lasting effects on real economic activity. Over the medium to long run,
economic growth and unemployment would tend to return to rates that were determined
by productivity growth, population dynamics, and other characteristics of the markets for
goods and labor.
To illustrate, suppose a policymaker consults a Phillips curve estimated from historical
data that tells him that 3 percent unemployment can be achieved at 5 percent inflation. If
the policymaker then eased interest rates in order to bring unemployment down, the
policy might initially have the intended effect, provided the public continues to expect the
lower previously prevailing inflation rate. But, the Friedman-Phelps framework argues, a
sustained effort to reduce unemployment by maintaining inflation at 5 percent would
ultimately lead the public to adjust their expectations for inflation. In the long run,
unemployment would rise again to its “natural” level consistent with the real structure of
the economy. Monetary policy can only have a transitory effect on unemployment.
In retrospect, many observers have labeled the Friedman-Phelps analysis prescient. They
point to the 1970s as a confirmation of the implications of the expectations-augmented
Phillips curve, because the period of high and volatile inflation in the 1970s brought no
sustained improvement in real economic activity. In fact, not coincidentally, the general
performance of the real economy during that period was poor.
The analysis of Friedman and Phelps focused attention on the critical macroeconomic
role of expectations. They assumed adaptive expectations, meaning that households and
firms based their expectations of future inflation on their observations of recent past
inflation. (For example, models of that era frequently represented inflation expectations
as a simple weighted average of past inflation.) In this view, an increase in the inflation
rate may catch people by surprise, but over time they would learn about the altered policy
stance. But why wouldn’t people try to look ahead and foresee what the central bank was
likely to do, rather than rely on the mechanical adaptive-expectations forecasting
formula? For example, why wouldn’t they expect the central bank to try to exploit a
short-run Phillips curve, even before inflation rises? Such anticipation could rob
inflationary policy of even its short-run stimulative effects.
In 1972, Robert Lucas provided an alternative, rational expectations analysis of the
relationship between inflation and real activity. Under rational expectations,
3
people’s expectations are based not just on their past observations, but also on their
assessment of how the economy is likely to behave, including their knowledge of the
process driving policymakers’ choices. The rational expectations analysis retained the
Friedman-Phelps implication that only unexpected inflation would be associated with
falling unemployment. But rational expectations implies that the public’s reaction to
policy is more forward looking than in the case of adaptive expectations.
In separate work, Lucas also showed how rational expectations presented a challenge to
making policy choices based on statistical estimates of such relationships as the Phillips
curve. 6 In what has famously become known as the Lucas Critique, he showed that shifts
in the pattern of policy behavior would cause such relationships like the Phillips curve to
shift as well, so that statistical estimates from historical data would no longer be relevant
for predicting the economy’s response to changing policy.
Later in the 1970s, Finn Kydland and Edward Prescott built on Lucas’ work and analyzed
the problem faced by a policymaker when the public is forward-looking. 7 They studied
the temptations faced by a central bank choosing policy period-by-period. In any given
period, what the public expected the central bank to do has already been determined.
Given those beliefs, the policymaker can pull down unemployment with a little more
unanticipated inflation. But people understand that the policymaker will be tempted to
induce unanticipated inflation, and thus they don’t believe prices will be stable – the
inflation will be anticipated. The result is higher inflation with no gain in real activity.
What the policymaker would like to do is find a way to commit to price stability, that is,
commit to not give in to the temptation to attempt to reduce unemployment by inducing
unanticipated inflation. The work of Kydland and Prescott highlighted to role of a central
bank’s credibility, in other words, the extent to which the public believes their
commitment to price stability. Their work highlights the extent to which establishing
credibility requires, indeed is virtually identical to, sacrificing future flexibility.
The linchpin of the link between inflation, unemployment and monetary policy is thus the
public’s expectations for inflation. If a run-up in inflation has been correctly anticipated,
then it up will have little or no effect on unemployment. Similarly, if people expect
falling inflation, then unemployment will not increase as much as it would if the
disinflation were unanticipated. Thomas Sargent demonstrated this dramatically in his
analysis of the ends of hyperinflations in a number of countries. 8 Very large reductions in
inflation were achieved at much less cost than would be predicted by a standard Phillips
curve, when those reductions were part of a comprehensive package of monetary and
fiscal reforms.
The role of expectations figured prominently in the disinflation that took place in the
early 1980s under Fed Chairman Paul Volcker. The Fed had delayed taking strong
enough action against inflation before Volcker took office in 1979, in part out of a belief
that the slope of the Phillips curve was such that a fairly large increase in unemployment
would be required to reduce inflation. The cost of the Volcker disinflation turned out to
be substantially less than predicted however. The recent release of the FOMC transcripts
4
from that era reveals that the public’s inflation expectations were quite prominent in the
Committee’s discussions. 9
The Modern Phillips Curve
Prior to the 1970s and 1980s, a significant methodological divide separated
macroeconomics and microeconomics. That divide broke down when economists
learned how to study models of the aggregate economy that were built on sound
microeconomic foundations – general equilibrium models, in other words – but were also
capable of addressing macroeconomic issues. The latter required models that were
dynamic, because investment and interest are central to macroeconomics, and stochastic
as well, because business cycle fluctuations seem to be to some extent unanticipated. 10
The first generation of such models had no substantive interaction between inflation and
real economic activity, and they displayed business cycles that were driven entirely by
real phenomenon. The challenge was to build models that captured the inflationunemployment link in a compelling way.
The modern Phillips curve emerged out of one approach to understanding the links
between inflation and real economic activity in such well-grounded models. The
approach involves specifying price-setting frictions that make a firm’s choice of the price
of its goods a dynamic decision that depends on expectations of future inflation. In
addition, a monopolistic competition feature provides firms with the scope for
meaningful price setting decisions. Under common forms of this friction, only a fraction
of sellers reset their prices each period. Anticipating a length of time before the next
opportunity to adjust their price, sellers will choose a price depending on what they think
will happen to the overall level of prices during that interval. Aggregating across sellers,
one finds that current prices (and thus current inflation) depend on expected future
inflation. 11 This comports with common sense intuition – money has value only because
it is expected to have value in the future. So the value of money today depends on value it
is expected to have in the future.
In this class of models, current inflation also depends on real economic variables,
particularly the real marginal cost of production, since relative prices are set as markups
over marginal costs. Under certain heroic assumptions, a one-for-one relationship
emerges between the real marginal cost of production and a measure of the scale of
aggregate economic activity, like output or the unemployment rate. That case results in
an equation one could describe as a Phillips curve, relating current inflation to current
real activity and expected future inflation. 12
Although this approach has broad acceptance, in fairness I should note that it is not
without its critics. Some economists view the price-setting frictions that are at the core of
this approach as ad hoc and unpersuasive. Moreover, there are alternative frictions, such
as spatial separation and limited information, that can also rationalize monetary nonneutrality. Nonetheless, a Phillips curve derived from price-setting frictions has become
the leading model for applied central bank policy analysis.
5
This modern form of the Phillips curve closely resembles the expectations-augmented
Phillips curve I discussed earlier, and thus shares many of the same properties. For
example, a marked movement in inflation will be associated with a move in
unemployment only if the inflation is different from what the public expected.
Furthermore, inflation expectations in these models are forward-looking, so expected
inflation, just like inflation itself and unemployment, is an endogenous variable
determined by the interaction of the conduct of monetary policy with private sector
decisions and shocks to the economy.
When economists take this new Phillips curve to the data, they often find that past
inflation helps explain inflation dynamics, even after attempting to control for expected
inflation. This finding has led some to formulate versions of the Phillips curve in which
both forward-looking and backward-looking price-setting behavior play a role. 13
Backward-looking price-setters are assumed to form expectations as a weighted average
of past inflation, consistent with the old adaptive expectations assumption in Friedman
and Phelps, or else set prices using a simple rule of thumb based on recent inflation
which amounts to the same thing.
This so-called “hybrid” Phillips curve implies an intrinsic persistence to inflation, beyond
that implied by the persistence of external shocks, the effect of expected inflation on
current inflation, or the conduct of policy. Moreover, in the presence of significant
backward-looking price-setting behavior, inflation would be prone to respond more
slowly to changes in policy. Consequently, a backward-looking component implies that
the real economic costs of bringing down inflation may be higher than would the case
with a purely forward-looking Phillips curve. For the same reasons, backward-looking
features would mean that inflation does not respond as rapidly to a change in policy as it
otherwise might, even if that change itself is well explained by the policymaker and well
anticipated and understood by the public.
In these so-called “hybrid’ Phillips curves, the extent to which price-setting and
expectations are backward looking can matter a great deal for monetary policy. As a
result, a small cottage industry of economists is now devoted to estimating hybrid Phillips
curves to try to find the appropriate weight to put on backward-looking price-setting.
Common estimates are that around 25 percent of agents form expectations in a backwardlooking fashion, although estimates of up to 60 percent have been obtained. Many such
estimates assume that the conduct of monetary policy has been constant over this period,
in the sense that it was guided by a single consistent pattern of behavior. If instead one
allows for the possibility of shifts in monetary policy, then the estimated weight on a
backward-looking component in the Phillips curve is far lower – in fact, often zero. The
intuition is straightforward. By not allowing persistent swings in monetary policy, the
standard approach can mistakenly attribute inflation persistence to backward-looking
expectations. The observed persistence of inflation thus might arise from forward-looking
behavior combined with uncertainty in the public’s mind about policy trends. If people
are uncertain about the policymaker’s objectives or strategy, then their inflation
6
expectations will adjust more slowly as they learn about these features of policy by
observing actual policy outcomes.
Policy
While there is reasonably strong statistical evidence of shifts in monetary policy,
the premise that inflation expectations are forward-looking and that the conduct of
monetary policy has evolved over time is also broadly consistent with the postwar history
of U.S. monetary policy. Moreover, that history is intimately intertwined with the
evolution of our understanding of the relationships embodied in the Phillips curve. 14
Widely held views about the Phillips curve in the 1960s suggested that tolerating a small
amount of inflation would allow permanently lower unemployment. As trend inflation
steadily rose into the early 1970s, the public came to expect higher inflation to persist and
the Phillips curve shifted out. Policymakers had overlooked the endogeneity of inflation
expectations, and their influence on future inflation outcomes. In the 1970s, policymakers
were reluctant to attack inflation aggressively out of a belief, based on the estimated
slope of the Phillips curve, that high sustained unemployment would be required to
reduce inflation. Belief in backward-looking expectations led policymakers to
underestimate the extent to which they could influence the evolution of expectations and
thereby reduce the cost of disinflation. Unemployment did increase during the
disinflation that Chairman Volcker initiated in 1979, but by substantially less than had
been predicted by backward-looking Phillips curves. On several occasions after that,
identified as “inflation scares” by my former colleague Marvin Goodfriend, inflation
expectations rose and the Fed responded aggressively by raising real interest rates above
what otherwise would have been warranted. 15 These episodes helped gain credibility for
the Fed’s commitment to low inflation. Realized inflation fell in the 1990s. Between
November 1995 and March 2004 (except for a six-month period around September 11,
2001), 12-month core PCE inflation was between 1 and 2 percent. The stabilization of
inflation expectations at low levels was crucial to that success.
I have given you an overview of the evolution of economists’ understanding of the
Phillips Curve, that is, the links between inflation and unemployment. To briefly
summarize, the Phillips curve began life as an atheoretical relationship, drawn to fit
historical correlations. It then became a static menu of inflation-unemployment options
available to policymakers. But that approach neglected the dynamic, forward-looking
nature of the decisions underlying the observed statistical relationship. The static Phillips
curve broke down in the late 1960s and 1970s, just when policymakers began to rely on
it, and in fact partly because they began to rely on it. The Phillips curve relationship was
rebuilt from first principles in 1980s and 1990s. In the resulting modern Phillips curve the
forward-looking expectations of price-setters plays a dominant role.
The modern Phillips curve has several important implications. First, the conduct of
monetary policy is best understood as a pattern of behavior, or a “rule” in the broad sense
of the word, not necessarily an algebraic formula. This contrasts with the view of
monetary policy as a sequence of one-shot choices of policy rate that was inherent in the
7
early version of the Phillips curve and the way my students were thinking about it. The
reason it makes sense to think of policy this way is that expectations about future policy
play a key role in the decisions people make today.
An immediate corollary is the importance of credibility, because low and stable inflation
today requires that people believe inflation will be low and stable in the immediate
future. And it deserves emphasis that credibility means giving up some flexibility in the
future. Another immediate corollary is the value of central bank communications,
especially communications aimed at helping people understand likely future outcomes for
inflation. The value of communications is what has led several central banks to announce
explicit numerical objectives for inflation.
The central theme, however, is that just as central banks are now widely acknowledged to
be responsible for the behavior of inflation, they are just as responsible for the behavior
of inflation expectations, because expectations are central to inflation dynamics. Related,
central banks should not take expectations for granted by acting in ways that are
inconsistent with those expectations, without taking into account that those expectations
may change as a result. For example, economists have detected a decline in inflation
persistence – that is, an increase in the tendency for inflation to return to trend after a
deviation from trend. One might be tempted to count on inflation to return to trend more
rapidly now, and infer that less policy response is needed when inflation departs from
trend. But the fall in persistence surely reflects the fact that policy reacts more forcefully
than before. Thus, a more rapid reversion to trend may be predicated on an implicit belief
that the Fed will act to bring that about. Failing to do so risks a shift in expectations that
makes inflation less likely to revert to trend.
The modern Phillips curve is particularly relevant to the dilemma I posed for my business
school students, that is, for evaluating alternative policy strategies for restoring price
stability. Would reducing inflation require large increases in unemployment? Again, the
key is the behavior of inflation expectations, which now seem to hover between 2 and 21/2 percent, a bit below inflation itself, and somewhat higher than rates consistent with
price stability. One might be pessimistic about the Fed’s ability to reduce inflation below
2 percent without significant increases in employment if one takes the current level of
inflation expectations as given. On the other hand, a strategy of clear and forceful
communications about policy intentions, if successful, could bring inflation and inflation
expectations down at significantly less cost. In this case, a more rapid return to price
stability could be achieved, and would require less unemployment and less policy
tightening than would otherwise be the case.
How responsive are inflation expectations to policymaker influence? General
prescriptions should not be expected, since results will depend on the nature of central
bank communication, the actions that accompany them and the context in which they are
received. There are many examples of significant shifts in expectations induced by
convincing people of a break from past practice. Examples include the fiscal reforms
accompanying the ends of hyperinflations I mentioned earlier, the operational regime
shift adopted by the Volcker FOMC in 1979, and the adoption of explicit inflation
8
objectives by several foreign central banks. In many recent instances, FOMC actions or
statements have induced short-run movements in market participants’ expectations
regarding the path of the federal funds rate and inflation. Fall 2005 and spring 2006 stand
out as noteworthy examples. Although there may be no precise historical analogs for
potential communications and actions to restore price stability in circumstances like the
present day, these examples suggest, to me at least, that policymakers can have a
significant effect on inflation expectations.
In any case, the centrality of inflation expectations in the modern Phillips curve
reinforces the importance of consistency and credibility in monetary policymaking,
since these are traits that reduce people’s uncertainty about future policy and stabilize
expected inflation. Central banks should not underestimate the degree to which they are
capable of influencing the evolution of inflation expectations. To paraphrase the late
Milton Friedman, inflation is always and everywhere an expectational phenomenon. To
put it another way, inflation expectations are an outcome of monetary policy, not an
autonomous help or hindrance. Central banks are as responsible for the behavior of
inflation expectations as they are for the behavior of inflation. That recognition is the key
to sound monetary policy.
Again, thank you for inviting me to speak here today.
1
John Weinberg contributed to these remarks.
Phillips (1957).
3
Lucas (1996), Humphrey(1991).
4
Samuelson and Solow (1960).
5
Friedman (1969), Phelps (1969).
6
Lucas (1976).
7
Kydland and Prescott (1977).
8
Sargent (1986)
9
Goodfriend and King (2005).
10
Kydland and Prescott (1982).
11
King (2000)
12
Some in the literature refer to this as the “New Keynesian Phillips Curve,” and to the underlying model
as the “New Neoclassical Economics.”
13
Gali and Gertler (1999).
14
Thomas Sargent and others have argued that it was changes in understanding of the Phillips curve that
drove swings in Fed policy over this period. Sargent(1999), Cogley and Sargent (2005), Sargent, Williams
and Zha (2006),.
15
Goodfriend (1993).
2
9
References
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Robustness to Model Uncertainty.” European Central bank Working Paper 478,
2005.
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1968, 58.1
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Journal of Monetary Economics, 1999, 44.2.
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Federal Reserve Bank of Richmond Economic Quarterly, Winter 1993, 79.1.
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_______________________. “Time to Build and Aggregate Fluctuations.”
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_____________. The Conquest of American Inflation. Princeton University Press,
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Cite this document
APA
Jeffrey M. Lacker (2007, April 10). Regional President Speech. Speeches, Federal Reserve. https://whenthefedspeaks.com/doc/regional_speeche_20070411_jeffrey_m_lacker
BibTeX
@misc{wtfs_regional_speeche_20070411_jeffrey_m_lacker,
author = {Jeffrey M. Lacker},
title = {Regional President Speech},
year = {2007},
month = {Apr},
howpublished = {Speeches, Federal Reserve},
url = {https://whenthefedspeaks.com/doc/regional_speeche_20070411_jeffrey_m_lacker},
note = {Retrieved via When the Fed Speaks corpus}
}