U.S. staffing companies employed an average of 2.9 million temporary and contract workers per day in 2012, up 4.1 percent from 2011, according to data released by the American Staffing Association.

In 2012, U.S. staffing firms hired 11.5 million temporary and contract employees over the course of the year.

In the fourth quarter of 2012, average daily staffing employment totaled 3.0 million workers, up 1.9 percent from the third quarter and up 1.0 percent from the fourth quarter of 2011.

The ASA staffing employment and sales survey is conducted on a quarterly basis, covering approximately 10,000 establishments.