Administaff Inc. (NYSE: ASF) posted an 11.6% increase in second-quarter revenue to $420.5 million from $376.8 million in the same period last year.

The Houston-based professional employer organization said revenue was boosted by a 7.2% increase in the average number of worksite employees to 116,149 and a 4.1% increase in revenue per worksite employee to $1,207.

Gross margin narrowed to 20.0% from 20.8%.

Net income fell 19.5% to $11.0 million from $13.6 million in the second quarter of 2007.

Administaff Inc. (NYSE: ASF)
For the second quarter ended June 30, 2008, compared with the same period in 2007.
Revenue: $420.5 million, +11.6%
Net income: $11.0 million, -19.5%