Professional employer organization revenue at Automatic Data Processing Inc. (NASD: ADP) rose 9.0% to $311.2 million in its fiscal second quarter ended Dec. 31, 2009, compared with $285.4 million in the same period last year.

ADP reports PEO revenue net of direct pass-through costs such as wages and payroll taxes.

 The average number of paid PEO worksite employees rose to 200,000 in the second quarter from 193,000 in the same period last year.

The company expects high single-digit revenue growth in its PEO services business in fiscal 2010.

PEO services represent just one of Roseland NJ-based ADP's service lines, which include nonstaffing services. Total second-quarter revenue at ADP was $2.20 billion, about flat with the year-ago quarter.