In the USA, the rate of
unemployment in May 2014 is 6.3%. Two
years ago, we foresaw the rate to fall down to 6% [±0.4%] in the fourth
quarter of 2013 or in the first
quarter of 2014. According to our model, this dramatic fall from the level
observed in 2012 is driven by the change in labor force and inflation. We
foresee the rate of unemployment to fall down to 3% [±0.4%] in the beginning of
2015. In this post, we discuss the bottom rate of unemployment. The USA will
meet a new situation with the smallest rate of unemployment since the late
1960s and low inflation. The performance of our original model is exiting.
In 2006, we developed
three individual empirical relationships between the rate of unemployment, u(t), price inflation, p(t), and the change rate of labour
force, LF(t), in the United States.
We also revealed a general relationship balancing all three variables. Since
measurement (including definition) errors in all three variables are
independent it may so happen that they cancel each other (destructive
interference) and the general relationship might have better statistical
properties than the individual ones. For the USA, the best fit model for annual
estimates was a follows:
u(t) =
p(t-2.5) +
2.5dLF(t-5)/dtLF(t-5) + 0.0585 (1)
where inflation (CPI) leads unemployment by 2.5
years (30 months) and the change in labor force leads by 5 years (60 months).
We have already posted
on the performance of this model several times.
For the model in this post, we
use monthly estimates of the headline CPI, u, and labor force, all reported by
the US Bureau of Labor Statistics. The time lags are the same as in (1) but
coefficients are different since we use month to month-a-year-ago rates of
growth. We have also allowed for changing inflation coefficient. The best fit
models for the period after 1978 are as follows:
u(t) = 0.63p(t-2.5) +
2.0dLF(t-5)/dtLF(t-5) + 0.07; between 1978 and 2003
u(t) = 0.90p(t-2.5) +
4.0dLF(t-5)/dtLF(t-5) + 0.30; after 2003
There is a structural break in
2003 which is needed to fit the predictions and observations in Figure 1. (This
break is purely artificial because it was induced by new statistics of labor
force and inflation introduced in 2003 by the Bureau of Labor Statistics. The
same effect was in 1978, when main definitions of labor force, unemployment,
and inflation were revised.) Due to strong fluctuations in monthly estimates of
labor force and CPI we have to smooth the predicted curve with MA(24). As a
result, the prediction horizon decreases from 30 to 18 months.
Figure 1 depicts the predicted
and observed rate of unemployment since the beginning of the 1960s. Figure 2
depicts the observed and predicted rate of unemployment since 2000, including a
forecast for the next 18 months. The model showed that the unemployment rate
will fall to 3.0 % in the beginning of 2015. For 119 observations since 2003,
the modelling error is 0.4% with the precision of unemployment rate measurement
of 0.2% (Census Bureau estimates in Technical Paper 66).
Hence, one may expect 3.0% [±0.4%].
Figure 1. Observed and predicted
rate of unemployment in the USA.
Figures 2. The predicted rate of
unemployment. We expect this rate to fall down to 3.0% [±0.4%] in the beginning 2015.