The American Staffing Association staffing index rose to a reading of 89 in May, up from 86 in April, the organization reported today. The index reading was 19% higher in May 2010 than in May 2009.

The index measures changes in the number of temporary and contract workers, both weekly and monthly. The monthly measure is taken from the week containing the 12th of the month. Its baseline value of 100 was set in June 2006.