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Full employment, or the natural rate of unemployment, is considered to be consistent with a level of unemployment that predominantly comprises voluntarily unemployed workers. In other words, those members of the labor force who really want a job have one. Leaving the nuances of who is part of the labor force for the main text, the rate of unemployment consistent with full employment is a major issue for economic policymakers. Small differences in the perceived rate of full employment lead to significant variations in the policy response to economic growth.
The definition of full employment is critical, because as unemployment rates reach and fall below this level, inflationary pressures start to build. The further that the unemployment rate falls below the natural rate, the greater the pressure on inflation. This is a result of modern production methods. Even in a capital-favoring production country like the United States, worker wages represent over 70% of all production costs. Rising wages increase costs, which are usually passed on to consumers as price increases, leading to climbing inflation.
To understand the relationship between full employment and wage increases, let us assume that the agreed upon natural unemployment rate is 5%. If the unemployment rate is 8%, then there are workers who desire jobs but cannot obtain one (known as involuntary unemployment). With high unemployment rates, the existing labor surplus implies that employers have little trouble finding people to work at the prevailing wage. But as economic growth accelerates, the labor surplus diminishes as more workers are hired, and the unemployment rate falls. Finally, due to strong economic growth, the unemployment rate falls to a level consistent with full employment.
As the story unfolds, economic growth remains persistently bullish, but now everyone (give or take) who wants a job has one. Yet increases in the demand for labor continue to grow and employers must pay existing workers overtime and entice non-labor force participants into the labor force by offering them higher wages. As wages increase, more people are willing to work (reaching their reservation wage), but production costs rise. If strong economic growth persists, wages pressures continue to build, leading to increasing inflation (also known as cost-push inflation).