That's up 7.7% from the first quarter and up 21.1% from the second-quarter of last year. However, Census Bureau numbers differ from other estimates.

In a basket of 10 of the largest publicly traded staffing firms tracked by Staffing Industry Analysts, second-quarter revenue rose by a median 15.3% from the year-ago quarter. Among all 30 public staffing firms tracked by Staffing Industry Analysts, second-quarter revenue rose by a median 15.4% on a year-over-year basis.

Staffing Industry Analysts estimated that total staffing industry revenue will rise by 6% for the full year of 2010.

The employment services category measured by the Census includes employment placement agencies, executive search firms, temporary employment agencies and professional employer organizations.