Moreover, temporary workers also were fired more aggressively during the recent recession than they were in the recession during the early 1990s. At that time, just 4% of jobs lost were temporary, but this time around 10.8% of firings were aimed at temporary workers. It helps to compare temporary workers to total private sector workers on a historical basis:

This chart shows a couple of important things. First, you can see that temporary workers (pink line) rose and fell at a relatively similar pace to all workers (blue line) leading up to the 2001 recession. Afterward, these two lines again began to track one another again, until the recent recession began coming on. At that time you see temporary workers take a huge dive from 2007 through mid-2009. The proportional decline is far more drastic than that of overall workers. The temporary workforce fell by 33.7%, while the overall private workforce fell by just 5.8%.

Consequently, the temporary workforce began to grow again, rapidly. That makes sense, since it had been so decimated during the recession. It's worth noting, however, that on this chart the temporary workers line lies below the private workers line as of November 2010, though during non-recessionary times it has generally been above it since 1990. In other words, temporary workers probably need to rise even more to return to equilibrium.

Tracking the portion of the private sector which consists of temporary workers reveals precisely that point. Here's another chart:

Prior to the recession, the portion of temporary workers were pretty steady around 2.3%. Only in June 2010 did it increase back to this level, after falling as low as 1.6% in 2009. Again, this shows that we shouldn't be alarmed at the level of temporary hiring yet. If it rises past 2.5%, then perhaps there could be cause for concern.

Even looking beyond the severity of temporary worker layoffs compared to that of permanent workers, it makes theoretical sense that this labor market recovery has been dominated by temporary hires. This recession was so long and so deep, and the recovery so fragile, that firms are being extra cautious when hiring back permanent staff. Only over the past few months have economists begun lowering the probability of a double dip recession in their forecasts. In this sort of very slow recovery, firms should be expected to hire more temporary workers.

The second chart above does, however, show something else. There appears to be a broader trend that began to form in the mid-1990s. Prior to that time, the portion of temporary workers was pretty consistent around 1.3%. But something changed. At that time, the temporary worker portion of the labor market rose to above 2.0%, which would become the new standard going forward. If there's really a question to be asked regarding the rise of temporary workers, it wouldn't be about this recession and recovery, but about what happened in the mid-1990s. That's when firms began staffing 50% more workers as temporary.

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