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Federal Reserve Bank of Chicago

Recent Evidence on the Relationship
Between Unemployment and Wage
Growth

By: Daniel Aaronson and Daniel Sullivan

WP 2000-27

Recent Evidence on the Relationship Between Unemployment and Wage Growth

Daniel Aaronson
Federal Reserve Bank of Chicago
Daniel Sullivan
Federal Reserve Bank of Chicago

December 2000

Abstract
The current expansion has delivered the lowest unemployment rates in decades, yet nominal
wage growth has remained relatively contained. This suggests to some a shift in the historical
relationship between unemployment and wage growth. We look across the states for more timely
evidence of a change in this relationship. We find some evidence that the elasticity of real wage
growth with respect to unemployment has fallen recently, a result that is not due to a compositional
shift toward college-educated workers. However, evidence of a weakened relationship is itself
weak, depending on inherently arbitrary decisions about when a shift may have occurred. In
addition, we find that levels of real wage growth associated with high, medium, and low
unemployment have remained relatively constant.
JEL Code: J30, E24

We thank Abigail Waggoner and Ken Housinger for research assistance. The views expressed in
this paper are solely those of the authors and are not official positions of the Federal Reserve Bank
of Chicago or the Federal Reserve System.

I.

Introduction
The long economic expansion of the 1990s has delivered the lowest unemployment rates in

30 years. Yet nominal wage growth has remained relatively contained. This failure of wages to
accelerate more rapidly suggests to some a shift, or even a complete breakdown, in the historical
relationship between unemployment and wage growth.1 However, looking across the years, the
relationship between unemployment and wage growth has always been relatively loose, implying
that it might take many years to conclusively identify even a significant change in the link between
unemployment and wages.
In this paper, we look across the states for more timely evidence of a change in the
relationship between unemployment and real wage growth. A major advantage of the cross-state
approach is the greatly increased number of degrees of freedom available from the wide variation in
state unemployment rates. Thus, it may be possible to identify changes in that response that would
take many years of time-series data to uncover. Previous work has demonstrated a relationship
between unemployment and real wage growth across states that is analogous to that in time-series
data.2 The basic assumption underlying this work is that inflation expectations are approximately
the same for all states in a given year. Given that the U.S. has a single, national monetary policy,
this is plausible, though clearly one could imagine deviations from this assumption. If inflation
1

Speculation about a change in the relationship between unemployment and wage growth has taken a number of forms,
not all of which have been well reasoned. Media analysts sometimes have characterized the lack of greater acceleration
of nominal wages in the face of low unemployment as a failure of the "forces of supply and demand" in the labor
market. But, the forces of supply and demand have direct implications for real, not nominal, wage growth (e.g.,
Friedman 1968). Among the few papers offering evidence of a break down in the unemployment – wage growth
relationship is a study by Lehrman and Schmidt (1999) suggesting that the level of unemployment across states is not
now related to wage growth. Footnote 14 below documents why we believe those authors' results differ from ours.
2
An important reference is Blanchflower and Oswald (1994), who document a cross-sectional relationship between
unemployment and wages in a number of countries over a number of periods. Blanchflower and Oswald interpret their
results as a relationship between unemployment and the level of wages because in their statistical models for the wage
level, lagged wages are estimated to have small coefficients. We agree, however, with Blanchard and Katz (1997) and
Card and Hyslop (1996) that these low estimates are the result of substantial measurement error in Blanchflower and
Oswald's wage measures as well as their inappropriate use of annual, rather than hourly earnings. We find that in
models employing hourly wage measures obtained from samples large enough to minimize measurement error, the
coefficient on lagged wages is quite close to unity. Thus, the relationship is best thought of in terms of wage growth

expectations are constant across states, differences in wage growth across states in a given year are
unrelated to inflation expectations. Similarly, to the extent that other variables, such as productivity
growth, that affect wage growth are constant across states in a given year, comparisons of states'
wage growth rates are also unaffected by these variables.
Our empirical work confirms the negative cross-state correlation between unemployment
and wage growth. We also find that the elasticity of wages with respect to unemployment has fallen
recently, a result that does not seem to be the result of a compositional shift toward collegeeducated workers. However, we regard this evidence of a weakened relationship between
unemployment and wage growth as itself weak. In particular, when we estimate an elasticity for
each year from 1980 to 1999, there is enough year-to-year variability that a downward trend in the
magnitude is not obvious. Rather, the extent of change observed in the relationship depends on the
necessarily arbitrary decision of where to draw the line between periods. Moreover, if one considers
the response of wage growth to the level of unemployment, rather than its logarithm, there is very
little evidence of a recent change in the sensitivity of wage growth to unemployment.
We also briefly examine how the level of wage growth associated with particular levels of
unemployment may have changed over time. We find that the levels of real wage growth associated
with high, medium, and low unemployment rates have been reasonably constant in recent years.
The real wage growth levels associated with typical values of unemployment were somewhat higher
in the early 1980s, but since then have been relatively constant, with the wage growth associated
with high unemployment rates actually rising somewhat in the late 1990s. Similarly, the
unemployment rate associated with the average rate of real wage growth fell after the early 1980s,
but has been relatively constant since then.

rather than wage levels. Roberts (1999) and Whelan (1999) show that the form of the micro-data relationship may not
matter for the form of aggregate inflation dynamics.

Finally, because there is no compelling theoretical reason for the standard civilian
unemployment rate to be the best measure of labor market conditions for predicting wage growth,
we also investigate a number of alternative measures of labor market tightness. Most of these
measures predict wage growth about as well as the standard unemployment rate. Most also show the
same decline in the magnitude of their elasticity with respect to wage growth that we observe over
five-year intervals for the unemployment rate. The decline in the coefficients associated with the
exit rate and short-term unemployment measures are, however, more severe.
Recently, there is evidence that typical short-run Phillips curve specifications have
systematically overforecasted inflation. Our results point toward the conclusion that this failure of
the forecasts is most likely attributable to the part of the model linking price inflation to wage
growth rather than to a change in the relationship between expected real wage growth and
unemployment. This is consistent with the findings of Brayton et al. (1999), who show that
including variables related to the markup of prices over wages helps stabilize the Phillips curve.
II.

Background
Some shift in the relationship between unemployment and real wage growth in the 1990s

would not be terribly surprising. Among the many changes in the labor market in recent years, the
general drop in the level of job security, the aging of the work force, its higher levels of education,
the growth of temporary services employment, the use of fax machines and the Internet in job
search, and even the increase in the prison population could each be changing the relationship
between unemployment and wage growth.3
A rough indication of the time-series evidence on this question can be gleaned from figure 1,
a scatter plot of annual data on the excess of hourly compensation growth over the previous year's

3

Aaronson and Sullivan (1999) discuss the implications for wages of a drop in job security. Katz and Krueger (1999)
discuss reasons for a drop in the natural rate of unemployment.

CPI inflation versus the natural logarithm of the annual unemployment rate.4 The relationship
depicted in figure 1 is analogous to the wage equations in some macroeconometric models. It can
be motivated by assumptions that wages are set to exceed expected inflation by an amount that
depends on the unemployment rate and expected inflation is equal to the level of inflation in the
previous year.5
The figure shows that there is a loose, but reasonably clear, negative correlation between
unemployment and wage growth in excess of lagged inflation. The least squares regression line
shown in the figure slopes downward with an elasticity of -0.055 and an estimated standard error of
0.009.6 A line connecting the values from 1992 to 1999 highlights the data for the current
expansion, when the unemployment rate was falling from 7.5 percent to 4.2 percent. As can be
seen, the growth of hourly compensation was a percentage point or more below expectations each
year from 1993 to 1997. Though the data for the last two years have returned to the predicted line,
the cumulative loss of wage growth over the expansion has been significant.
However, such departures of wage growth from expectations are far from unprecedented. In
earlier years, the data have strayed further from expectations only to return to the basic pattern of
low unemployment being associated with higher growth of wages relative to lagged inflation. Of
course, the evidence also does not rule out a significant shift in the relationship between
unemployment and inflation. Unfortunately, given the looseness of the historical relationship, it
would take many years to confidently identify even a relatively large change in the relationship.
4

The compensation data is from the BLS's productivity and cost release. Results using the BLS's average hourly
earnings and employment cost index (ECI) series are somewhat similar, although the latter series is not as tightly
associated with unemployment. We use the productivity report's measure because it covers wage and nonwage forms of
compensation and goes back farther than the ECI. Abraham et al (1999) discusses the differences in these wage series.
5
Blanchard and Katz (1997) discuss the relationship between the kind of time-series evidence depicted in figure 1 and
the cross-state evidence that is the main focus of this article. Of course, wage equations in actual macroeconometric
models are considerably more elaborate than what is represented in the figure. In particular, they use higher frequency
data, allow for more complicated dynamics, and include other variables, such as the level of productivity. Blanchard
and Katz note that these other variables are often found to have little impact on wage growth forecasts.

Moreover, the theoretical basis for the relationship depicted in figure 1 is somewhat loose,
which at least suggests the possibility of instability. The assumption that expectations of inflation
are equal to last year's level of inflation is clearly ad hoc. Moreover, though a relationship between
expected real wage growth and unemployment can be motivated by economic theory, such theory
does not necessarily imply a special place for the standard civilian unemployment rate.
Indeed, in the simplest model of a competitive labor market, unemployment is not a welldefined concept because there is no distinction between workers being unemployed and out of the
labor force. Rather, in that model wages adjust to clear the market, and workers for whom the
equilibrium wage is below the alternative value of their time simply choose not to work. The
competitive model would replace the relationship in figure 1 with a standard, aggregate labor supply
curve. This is analogous to the relationship in figure 1, but with employment, rather than
unemployment, as the variable predicting wage growth. Of course, (deviations from trend)
fluctuations in these variables are highly correlated, so unemployment may predict expected real
wage growth reasonably well even if employment is the theoretically preferable measure.
Other models go beyond the simple competitive framework to allow involuntary
unemployment and the unemployment rate to be related to wages. For example, in search models
with wage bargaining, workers have greater bargaining power when the unemployment rate is low,
since turning down a job offer with a low wage is more palatable when the unemployment rate is
low (Mortensen and Pissarides 1994). Alternatively, efficiency wage arguments like Shapiro and
Stiglitz (1984) and Salop (1979) generate a link between unemployment and wages because when
unemployment is low, discharged workers will face less time out of a job. Thus, wages need to be
further above the value of workers' nonmarket uses of time to induce the same level of effort.

6

These were computed under the usual ideal assumptions that error terms are uncorrelated and of constant variance, and
thus may be somewhat optimistic. The hyperbolic lines around the regression line represent 90 percent confidence
intervals for the expected level of wage growth in excess of inflation at a given level of log unemployment.

Even in search and efficiency wage models, the standard unemployment rate may not be the
variable most directly related to wages (Blanchard and Katz 1997). Rather, in both classes of
models, the exit rate from unemployment is a more direct measure of the cost to workers of
becoming or staying unemployed than the unemployment rate itself, which also depends on the rate
of entry into unemployment. Of course, since the exit rate and the overall unemployment rate are
relatively highly correlated, the latter may predict wages reasonably well even if the former is the
variable that is truly linked to expected wage growth.
Even if one accepts the use of an unemployment rate as the measure of labor market
conditions, there is still the question of which unemployment rate to use. The standard measure
imposes requirements that nonemployed workers be available for work and have made an effort to
find work in the last month. However, some out-of-the-labor-force workers, for example, those who
say they want a job, are relatively similar to the unemployed and may exert an influence on wage
growth. Conversely, some of those who are unemployed, such as those who have been unemployed
for long periods, may be more similar to the out-of-the-labor-force pool.7 Ultimately, which
measure best captures the labor market forces influencing wages is an empirical question, the
answer to which could change over time.
III.

Data
Our main results are based on two data sources. The first is the annual averages of the BLS's

monthly, state-level unemployment rates. The second source is a measure of state-level,
demographically adjusted wage growth that we construct from the outgoing rotations (ORG) of the
Current Population Survey (CPS). We compute an individual's hourly wage as the ratio of weekly

7

Castillo (1998) shows that in U.S. data, those outside the labor force who want a job are less attached to the labor
market than unemployed workers. However, in Canadian data, Jones and Riddel (1999) show that those out of the labor
force who report wanting a job are closer to the unemployed than to others who are out of the labor force, in terms of
their subsequent probabilities of employment.

earnings to weekly hours of work.8 Pooled across the 12 months of the year, the ORGs yield an
annual sample size of at least 150,000 households. They are available from 1979 to 1999.
We summarize the individual-level wage data with an adjusted average wage for each stateyear pair. These are obtained as state-year-specific intercepts in a regression of the natural logarithm
of wages on demographic and educational characteristics:
ω ist = w st + x istβ + ηist ,

(1)

where ω ist is the log of the wage for individual i in state s and year t. The vector, x ist , of control
characteristics is the same as that utilized by Blanchard and Katz (1997) and consists of a quartic in
potential experience interacted with an indicator for sex, an indicator for marital status interacted
with sex, a nonwhite indicator, a part-time indicator, and indicators for four educational attainment
categories.9 The estimated w st coefficient is our measure of the adjusted log wage in state s and
year t.10
The ORG data are our preferred source of state-level wage data. Their main attractions are
large sample sizes and relatively rich associated demographic data. The lack of information on the
value of benefits is a potential limitation. However, it seems plausible that the difference in growth
rates between our measure and a more inclusive measure of total compensation is constant across
states in a given year. If this is the case, as we explain further below, our estimates of the sensitivity
of wage growth to unemployment will be unaffected. Nevertheless, to provide a check on the
sensitivity of our results to the value of benefits, we also make use of the regional detail of the ECI.
Finally, another limitation of the ORG data is that they are not available prior to 1979,
which might be considered a relatively short time series. Thus, in order to provide some evidence
8

We drop observations on workers whose computed wage is less than 50 cents per hour or more than $100 per hour.
Blanchard and Katz (1997) estimate separate regression models for each year of data while we estimate a single,
pooled regression. This makes no appreciable difference to the results when year effects are included in the estimation.
10
The correlation of our ORG measure is at least 0.72 with other aggregate wage measures, including average hourly
earnings, ECI, and compensation per hour. This is about as high as the other measures are correlated with each other.
9

on the sensitivity of wage growth to unemployment in earlier years, we also use the annual
demographic files from the March CPS.11 These contain responses to questions on earnings, weeks
worked, and usual hours per week in the previous calendar year. Thus, a wage rate can be calculated
as annual earnings divided by the product of weeks worked and usual hours per week.12 These data
are available starting in 1964, though prior to 1977, data from smaller states are not identified
separately. A drawback of the March data is the smaller sample size. Nationally, the sample is
around 50,000 households, but for small states, samples can be as small as a few hundred. This
tends to make the associated wage measures quite volatile from year to year. In addition, we are
forced to drop some of the early years because of changes in sample design.
IV.

Empirical results
The analysis is based on a standard statistical model for the response of wage growth to

unemployment. That model can be written as
(2)

∆w*st =α s + γ
t + ustβ + εst ,

where ∆w*st is adjusted wage growth and ust is the log of the unemployment rate for state s in year
t. The state-specific effects, α s , control for characteristics that are constant across time within a
state. The year-specific effects, γ,
t control for the level of expected inflation in year t, as well as
for the effects of productivity and other variables that may affect wages in a given year.
Year-specific effects may also control for the effects of the exclusion of the value of benefits
from our ORG-based measure of wage growth if the difference is constant across states for a given
year. Then ∆w st = ∆w*st + g t and equation 2 can be written as
(3)
11

′
∆w st =α s + γ
t + ustβ + εst ,

In our analysis of the March data, unemployment rates before 1978 are obtained from state unemployment insurance
claims data.

′
where γ
t =γ
t + g t . In this case, the lack of benefits information affects the estimates of the year
effects, but not the estimate of β .13 Moreover, if we can identify the true wage growth averaged
over all states for a year with a measure such as hourly compensation from the productivity report,
we can adjust the estimates of the year effects to be consistent with such data (i.e.
g t = ∆w t − ∆w *t ).
Table 1 reports estimates of β from equation (3). As shown in the first column of the first
row of table 1, the ordinary least squares estimate is -0.042 with a standard error of 0.004. The
second and third columns of table 1 present alternative estimation methods that reduce the influence
of outliers. The second column simply weights the observations by state employment while the third
column estimates the parameters using the biweight robust regression technique. We prefer the
latter method of estimation for its high degree of efficiency in the face of the kind of heavy-tailed
data that we employ. The first two digits of the estimates of the overall sensitivity of wage growth
to unemployment are unaffected by choice of estimation method. However, consistent with its
greater efficiency in the presence of outliers, the estimated standard errors from the robust
regression technique are slightly smaller than those for ordinary or employment-weighted least
squares.
Table 1 also shows estimates of the response of wage growth to unemployment for four fiveyear periods. The results suggest that wage growth has become somewhat less sensitive to
unemployment in the 1990s. The robust regression methodology yields estimates of -0.045 and
-0.044 for the early and late 1980s. The coefficient estimate for the early 1990s fell to -0.039 and to
-0.033 in the late 1990s. Of course, even in the late 1990s, the estimates in table 1 are statistically

12

Usual weekly hours is not available prior to 1976. In its place, we use hours worked in the week prior to the survey.
This argument goes through more generally if the difference between the ORG wage growth measure and an ideal
wage growth measure has an error components structure that is limited to a year effect, a state effect, and an error term
that is uncorrelated with unemployment.
13

significant, with t-statistics around five. But there is evidence that the coefficient has changed over
time. The F statistics shown in the table imply that the hypotheses that the 1995-99 coefficient is the
same as the 1980-84, 1985-89, and the 1980-94 averages can be rejected at the 10 percent level,
although not at the 5 percent level. The hypothesis that the 1995-99 coefficient is the same as the
1990-94 coefficient cannot be rejected at any standard confidence level.
Figure 2 shows the result of estimating a separate slope for each year of the sample. Such
estimates are based on the model
(4)

∆w st =α s + γ
t + ust βt + εst ,

which continues to impose a common state effect, but allows the intercept and slope to vary freely
over the sample period. Robust estimates of the slopes by year are plotted in figure 2 along with 90
percent confidence intervals. Since each data point is essentially estimated from 51 rather noisy
observations, the confidence intervals tend to be somewhat wide. Still, all 20 coefficients are
statistically significant at the 5 percent level.
The pattern of estimates shown in figure 2 leads us to view the evidence of a systematic drop
in the magnitude of the coefficient as somewhat weak. The magnitude of the elasticity has
decreased in recent years, with 1998 having the single smallest coefficient. But as recently as 1994
and 1995, the coefficient was about as large as it ever has been. And there have been previous years
-- 1985 and 1993 -- in which the coefficient has declined, only to increase again subsequently.
The drop in coefficients in table 1 is also dependent on the imposition of a constant elasticity
functional form. If instead, absolute differences in unemployment rates have the same effect on
wage growth no matter how high or low they are, then the specification estimated in table 1 will
force the coefficient for recent years, when unemployment has been relatively low, to fall, even if
there has been no change in the relationship between wage growth and the level of unemployment.
The fourth column of table 1, which contains estimates based on a common slopes, rather than

common elasticities, specification, contains some evidence in support of this hypothesis.
Specifically, with a common slopes specification, there is no evidence of a decline in the sensitivity
of wage growth to unemployment. Rather, the late 1980s appear to be the period that was different,
having a higher estimated coefficient than the other three periods. We prefer the constant elasticity
specification because of the better fit to the data, but the results in column 4 reinforce our view that
the evidence of a decline in the sensitivity of wage growth to unemployment is weak.
Table 2 explores the sensitivity of the results to alternative specifications. The first column
shows the slope coefficients when we include additional variables measuring the fraction of workers
in one-digit industries and occupations. Such variables may control for state variation in
productivity growth and other factors that determine wage growth. The coefficients tend to be
smaller in magnitude than those in table 1, but the conclusions one would draw are similar; while
the coefficient for the late 1990s is somewhat smaller, it is still highly statistically significant.
The next column in table 2 uses the unemployment rate from the year before rather than the
current year. This lowers the coefficients. The decline in the recent period is smaller, however. The
next three columns explore the sensitivity of the results to the inclusion of fixed effects. Leaving out
year effects makes the coefficients larger in magnitude, reflecting the fact that years with lower
unemployment have had higher than average wage growth. Leaving out state effects significantly
weakens the results, which reflects the fact that states with higher than average mean unemployment
rates tend to have higher mean wage growth. Leaving out both kinds of fixed effects produces weak
results as well. Both kinds of fixed effects are statistically significant according to the usual F
statistic. Thus, we prefer the specification estimated in table 1, and view the other results as
indicating the effects of various forms of specification errors.14

14

Lerman and Schmidt (1999) report no evidence of a cross-state association between unemployment and wage growth.
They use the ORG files to estimate state-specific wage growth between the first quarters of 1995 and 1998, computing
mean wage growth for four "quartiles" of the unemployment distribution in the first quarter of 1998. They find little or

One possible explanation for the falling coefficient on unemployment is the changing nature
of the work force. For instance, it is has been previously shown that wage growth among collegeeducated workers is less sensitive to unemployment than that among other workers. Thus, the
increasing share of college-educated workers could cause a decline in the unemployment coefficient
of the kind seen in table 1.15 The results in the last two columns of table 2, however, show that this
is not the case. The decline in coefficients is seen both for noncollege and college workers.16
Something other than a compositional shift towards college workers explains the lower late-1990s
coefficients on unemployment.
Table 3 shows estimates of our basic specification using the March CPS data. The results
shown for five year intervals between 1964 and 1998 suggest a quite stable relationship between
unemployment and wage growth, with elasticity estimates generally near -0.035 except for the 1984
to 1988 period when the elasticity was estimated to be -0.045. Moreover, the F-statistics indicate
that even the latter estimate is not statistically different from the estimate for the most recent period.
Finally, as a robustness check of the importance of benefits on the real wage-unemployment
relationship, we also looked at the regional ECI data. Because these data are available for only four
regions and date back to only 1983, there are many fewer degrees of freedom. However, the ECI
does allow us to look directly at the association between total compensation and unemployment.
While the results for ECI wages and salaries are relatively similar to those in table 1, for total
compensation, the coefficient for the most recent five-year period is small and not statistically
no association between unemployment quartile and wage growth. The results above may explain some of the difference
between their results and ours. Lehrman and Schmidt use the unemployment rate for only the last quarter of the period,
rather than the average over the whole period. The results in table 2 using lagged unemployment rates suggest that the
match of the time periods of unemployment and wage growth matters to the estimates. Lehrman and Schmidt also use
data on unemployment in 1998, which figure 2 says provides the weakest results of any year. Moreover, they only look
at a single cross-section of data and so cannot control for state-specific fixed effects which table 3 shows is important.
Finally, fitting a nonlinear specification seems to us to be asking a lot of 51 noisy observations. Clearly, there is a wide
scatter around what is still a highly significant negative relationship. Thus, it would be quite surprising to see a clean
pattern of means across quartiles when each of those means was estimated with only 12 or 13 observations.
15
Furthermore, Solon et al (1994) argue that, in aggregate time-series data, compositional bias arises because low-skill
workers are overweighted during expansions, leading to a downward bias in the procyclicality of real wages.

significant. However, looking closely at the individual observations suggests that a very small
number of data points are driving this result. Moreover, when we break the data into three-year
intervals, the results suggest less evidence of a drop in the sensitivity of total compensation growth
to unemployment. Therefore, given how little regional variation underlies the data, we consider the
consistency of the results with those in table 1 to be reasonably good.
Thus far, our results have been limited to showing how the sensitivity of wage growth to
unemployment has varied over time. Table 4 shows, in addition, how the level of wage growth
associated with any level of unemployment has varied over time. Such quantities depend on both
the estimated slope coefficients, βt , and the year effects, γ.
t The values shown are based on the
specification of table 1 in which slopes are constant for each five-year period. The values in the
column labeled Average Intercept-Raw are the average of the five-year effects ( γ
t s ) estimated for
′
the period. The adjusted values in the next column are our estimates of the γ
t , the values that
would correspond to the more comprehensive hourly compensation wage growth measure. The
intercept values are somewhat difficult to interpret because they potentially capture the effects of a
number of variables. However, the fact they have fallen over time is consistent with the notion that
they capture changes in expected inflation.
Given the normalization that ∑ α s = 0 , the predicted mean ORG-based adjusted wage
growth associated with log unemployment rate u t for year t is ∆w t = γ
t + u tβt , and the predicted
′
mean hourly compensation growth is ∆w*t = γ
t + u tβt . The predicted amount by which the growth
of hourly compensation exceeds the growth in business sector prices, which is a reasonable measure
′
of real wage growth, is ∆w*t − ∆p t = γ
t − ∆p t + u tβt , where ∆p t is the change in the log average
price deflator for the business sector. Table 4 shows the predicted average real wage growth
16

This pattern emerges when we use education-specific unemployment rates as well.

calculated in this manner for unemployment rates of 4 percent, 6 percent, and 8 percent. For an
unemployment rate of 4 percent, predicted real wage growth dropped between the early and late
1980s, but has been reasonably constant since then. Our estimates currently predict real wage
growth of 2.8 percent when the unemployment rate is 4 percent, about its current value. The
predicted real wage growth rates associated with 6 percent and 8 percent unemployment also fell
between the early and late 1980s, and since then have been fairly constant. The 0.6 percent level of
wage growth predicted for 8 percent unemployment in the last period has, however, returned to
about its level for the early 1980s.
One can also ask what level of unemployment is predicted to deliver a particular rate of real
wage growth, say ∆(w * / p) . According to the above, that unemployment rate is
u* = [∆( w * / p ) − ( γ
t − ∆p t )] / βt . The last column of table 4 shows the values of this quantity
corresponding to the mean real wage growth rate over 1980-99, which was about 1.5 percent per
year. That unemployment rate was nearly 7 percent in the early 1980s, but since then has been
relatively constant at about the 6 percent level that we estimate for the late 1990s. We view the
results in table 4 as confirming the relatively stable relationship between real wage growth and
unemployment.
Finally, we argued previously that other labor market variables might predict wage growth
better than the unemployment rate. The recent drop in the coefficient on unemployment seen in
table 1 might even reflect a misspecification in which unemployment is proxying for a more
appropriate measure of labor market conditions. The drop in the unemployment coefficient might
then be due to a lower correlation of unemployment with the preferred variable, which could have a
stable relationship to wage growth. The results in table 5 suggest, however, that the decline in the
coefficients in table 1 are not due to the unemployment rate becoming a poorer proxy for a superior
measure of labor market tightness. The table shows the results of replacing the unemployment rate

with several other measures of labor market conditions, including an ORG-based unemployment
rate, a measure of unemployment that includes those who say they want a job regardless of whether
they have recently searched, a broader unemployment rate that includes those who work part-time
for economic reasons, a narrower measure that includes only white males between the ages of 25
and 54, the employment-to-population ratio, a measure of the exit rate out of unemployment, the
fraction of the labor force unemployed five or fewer weeks, and the portion of the labor force
unemployed 15 or more weeks. Virtually all the measures show the recent decline in coefficient
magnitude that is seen in table 1. The drop off in the sensitivity of wage growth is especially
significant for the exit rate out of unemployment and the rate of short-term unemployment.
However, this may reflect the introduction of computer-aided interviewing technology with the
1994 CPS redesign, which had the effect of introducing a series break in short-term unemployment
measures.
The results in table 5 suggest that the standard unemployment rate is not the only measure
that might be used to judge the tightness of labor market conditions. Judging by the standard Rsquared measure, several variables predict wage growth about as well as the unemployment rate.
Indeed, the rate of long-term unemployment actually does very slightly better. The two broader
measures of unemployment, which include all of those who say they want a job and those workers
plus those who are involuntarily part-time, come reasonably close to matching the predictive power
of the standard unemployment rate, while the narrower measure that is limited to prime-age white
males does less well. Perhaps somewhat surprisingly, the measures that may be more closely
connected to theory, the employment-to-population ratio and the exit rate from unemployment, are
among the least well performing measures, though in the latter case this may be due to breaks in the
data series. A fully satisfactory comparison of the forecasting abilities of the various labor market

variables would require the use of higher frequency data, more elaborate dynamics, and some
attention to the out-of-sample properties of the forecasts.
V.

Conclusion
We have shown that the negative cross-state correlation between unemployment and wage

growth persists even in recent data. We find some evidence of a decline in the sensitivity of wage
growth to unemployment and other labor market measures in the late 1990s. But, we regard that
evidence as being somewhat weak because it is dependent on exactly when the line between periods
is drawn and whether the relationship is modeled as one in which percentage or absolute differences
in unemployment rates have constant effects on wage growth.
Our results have implications for work on inflation forecasting. Traditional short-run, or
expectations-augmented, Phillips curve methodologies have tended to overpredict the change in
inflation in recent years (Brayton et al. 1999). That methodology depends upon both the
relationship between unemployment and expected wage growth and the relationship between wage
growth and price inflation. Given the many fundamental changes that may be affecting the labor
market, it is natural to look for a change in the relationship between unemployment and wage
growth. But, our finding that the cross-state relationship between unemployment and wage growth
has been relatively stable suggests that more attention be given to the link between wage growth
and price inflation as the source of instability in the short-run Phillips curve. This seems consistent
with findings such as those in Brayton et al. (1999) that adding variables to account for variation in
the markup of prices over wages may be the most attractive way to stabilize the relationship
between unemployment and changes in price inflation.

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Table 1
State Wage-Unemployment Elasticities 1

WLS

OLS

Robust

Robust

Unemployment rate

-0.042 *
(0.004)

-0.042 *
(0.004)

-0.042 *
(0.003)

-0.0059 *
(0.0005)

Adjusted R-squared

0.467

0.550

0.463

0.450

Unemployment rate, 1980-84
Unemployment rate, 1985-89
Unemployment rate, 1990-94
Unemployment rate, 1995-99

-0.047
(0.005)
-0.046
(0.005)
-0.038
(0.006)
-0.032
(0.007)

*
*
*
*

-0.049
(0.005)
-0.046
(0.005)
-0.040
(0.007)
-0.030
(0.006)

*
*
*
*

-0.045
(0.005)
-0.044
(0.005)
-0.039
(0.006)
-0.033
(0.006)

*
*
*
*

-0.0053
(0.0007)
-0.0068
(0.0007)
-0.0063
(0.0010)
-0.0064
(0.0012)

F test p-statistic:
UR, 1980-94=UR, 1995-99
UR, 1980-84=UR, 1995-99
UR, 1985-89=UR, 1995-99
UR, 1990-94=UR, 1995-99

0.082
0.059
0.058
0.435

0.027
0.011
0.037
0.218

0.086
0.074
0.092
0.395

0.751
0.358
0.760
0.968

Adjusted R-squared

0.469

0.552

0.461

0.450

yes

yes

yes

no

Log of unemployment rate

Notes:

*
*
*
*

Table 2
State Wage-Unemployment Elasticities 1
Alternative Estimates

Industry and
Occupation
Controls

Unemployment rate, 1980-84
Unemployment rate, 1985-89
Unemployment rate, 1990-94
Unemployment rate, 1995-99

-0.042
(0.006)
-0.038
(0.005)
-0.034
(0.006)
-0.028
(0.006)

Lag
Unemployment
rate

*
*
*
*

-0.036
(0.006)
-0.038
(0.005)
-0.027
(0.006)
-0.030
(0.006)

No
Fixed
Effects

*
*
*
*

-0.016
(0.002)
-0.028
(0.003)
-0.028
(0.003)
-0.029
(0.003)

No Year
Fixed Effect

*
*
*
*

-0.034
(0.003)
-0.048
(0.004)
-0.048
(0.004)
-0.052
(0.004)

No State
Fixed Effect

*
*
*
*

-0.024
(0.005)
-0.030
(0.004)
-0.014
(0.005)
-0.012
(0.005)

Noncollege
Sample

*
*
*
*

-0.047
(0.006)
-0.046
(0.005)
-0.039
(0.006)
-0.035
(0.006)

College
Sample

*
*
*
*

-0.038
(0.011)
-0.037
(0.009)
-0.034
(0.011)
-0.027
(0.011)

F test p-statistic:
UR, 1980-94=UR, 1995-99
UR, 1980-84=UR, 1995-99
UR, 1985-89=UR, 1995-99
UR, 1990-94=UR, 1995-99

0.093
0.050
0.138
0.380

0.497
0.377
0.212
0.682

0.026
0.000
0.701
0.366

0.596
0.014
0.609
0.609

0.025
0.052
0.002
0.752

0.111
0.083
0.087
0.531

0.371
0.395
0.397
0.594

Adjusted R-squared

0.469

0.434

0.155

0.178

0.449

0.424

0.202

Notes:
*=significant at 5 percent level
1
UR= unemployment rate. All regressions include state and year fixed effects, unless noted, and are estimated using robust regression.

*
*
*
*

Table 3
State Wage-Unemployment Elasticities 1
Using the March CPS, 1964-98

Unemployment rate, 1964-68
Unemployment rate, 1969-73
Unemployment rate, 1974-78
Unemployment rate, 1979-83
Unemployment rate, 1984-88
Unemployment rate, 1989-93
Unemployment rate, 1994-98
F test p-statistic:
UR, 1964-93=UR, 1994-98
UR, 1964-68=UR, 1994-98
UR, 1969-73=UR, 1994-98
UR, 1974-78=UR, 1994-98
UR, 1979-83=UR, 1994-98
UR, 1984-88=UR, 1994-98
UR, 1989-93=UR, 1994-98

Time period
Adjusted R-squared

-0.034
(0.013)
-0.029
(0.014)
-0.039
(0.012)
-0.036
(0.009)
-0.045
(0.007)
-0.036
(0.009)
-0.036
(0.010)

*
*
*
*
*
*
*

0.834
0.900
0.644
0.879
0.990
0.482
0.971

1964-1998
0.414

Notes:
*= significant at the 5 percnet level.
1
UR=unemployment rate. Regression includes state and year fixed effects and is estimated using robust regression. The
unemployment rate is from the BLS for 1978-99 and state UI records for 1964-77. Some states are not uniquely identified in
the March CPS prior to 1977. Dates reference the previous year's CPS earnings question. For example, wage data for 1998
is from the March 1999 CPS.

Table 4
Wage Growth Function

Slope

Average Intercept
Raw
Adjusted

Real Wage growth Associated With
Unemployment Rate of
4%
6%
8%

Unemployment
Rate Consistent
with 1980-99
Average Real
Wage Growth

1980-84

-0.047
(0.005)

0.143
(0.011)

0.165
(0.011)

4.1
(0.4)

2.2
(0.2)

0.8
(0.1)

6.9
(1.7)

1985-89

-0.046
(0.005)

0.111
(0.008)

0.122
(0.008)

3.1
(0.2)

1.2
(0.1)

-0.1
(0.2)

5.6
(1.0)

1990-94

-0.038
(0.006)

0.097
(0.010)

0.107
(0.010)

2.8
(0.3)

1.3
(0.1)

0.2
(0.1)

5.7
(1.6)

1995-99

-0.032
(0.006)

0.084
(0.009)

0.086
(0.009)

2.8
(0.5)

1.5
(0.2)

0.6
(0.2)

6.0
(1.6)

Table 5
State Wage-Unemployment Elasticities
Alternative Labor Market Indicators

BLS
Unemp.
rate

ORG
Unemp.
rate

Unemp.
plus NILF
who want
job

Unemp.
plus NILF
who
want job
plus PT
for econ
reasons

1

White,
male,
age 25-54
unemp. rate

Emp-pop
ratio2

Exit rate
out of
unemp. 3

Unemp.
0-5 weeks3

Unemp.
15+ weeks

Unemployment
rate, 1980-84

-0.045 *
(0.005)

-0.043 *
(0.005)

-0.050 *
(0.006)

-0.058 *
(0.007)

-0.024 *
(0.004)

0.194 *
(0.029)

0.036 *
(0.007)

-0.025 *
(0.008)

-0.022 *
(0.003)

Unemployment
rate, 1985-89

-0.044 *
(0.005)

-0.042 *
(0.005)

-0.047 *
(0.005)

-0.051 *
(0.005)

-0.023 *
(0.003)

0.173 *
(0.028)

0.025 *
(0.007)

-0.036 *
(0.007)

-0.022 *
(0.003)

Unemployment
rate, 1990-94

-0.039 *
(0.006)

-0.035 *
(0.006)

-0.039 *
(0.007)

-0.038 *
(0.007)

-0.021 *
(0.004)

0.164 *
(0.030)

0.022 *
(0.006)

-0.001 *
(0.008)

-0.020 *
(0.003)

Unemployment
rate, 1995-99

-0.033 *
(0.006)

-0.027 *
(0.006)

-0.031 *
(0.006)

-0.029 *
(0.007)

-0.016 *
(0.004)

0.176 *
(0.030)

0.001 *
(0.002)

0.003 *
(0.006)

-0.014 *
(0.003)

F test p-statistic:
UR, 1980-94=1995-99
UR, 1980-84=1995-99
UR, 1985-89=1995-99
UR, 1990-94=1995-99

0.086
0.074
0.092
0.395

0.023
0.022
0.024
0.252

0.024
0.015
0.026
0.337

0.002
0.001
0.003
0.274

0.055
0.058
0.094
0.246

0.936
0.436
0.897
0.607

0.000
0.000
0.002
0.001

0.001
0.002
0.000
0.637

0.020
0.043
0.034
0.138

Adjusted R-squared

0.461

0.453

0.448

0.457

0.438

0.409

0.413

0.412

0.466

Notes:
*=significant at 5 percent level.
1
UR=unemployment rate. All regressions includes state and year fixed effects and are estimated using robust regression.
2
Detrended.
3
1994 is excluded.

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Figure 2
Annual Log Unemployment Rate Coefficients
0.00
-0.01
-0.02
-0.03
-0.04
-0.05
-0.06
-0.07
-0.08
-0.09
1998

1996

1994

1992

1990

1988

1986

1984

1982

1980

-0.10