Net income at Administaff Inc. (NYSE: ASF) fell 0.4% to $13.3 million in the fourth quarter of 2007 from $13.4 million in the fourth quarter of 2006.

The Houston-based professional employer organization reported a 10.7% increase in average number of worksite employees paid per month and a 3.0% rise in revenue per worksite employee per month. However, it said operating expenses per worksite employee per month rose 3.2% to $191 in the fourth quarter of 2007 from $185 in the same period in the prior year.

Revenue rose 14.0% to $402.1 million in the fourth quarter compared with $352.6 million in the same period in the prior year. Gross margin fell to 21.0% from 21.2%.

Full-year 2007 net income increased 2.1% to $47.5 million from $46.5 million in 2006.

2007 revenue rose 13.0% to $1.57 billion from $1.39 billion in 2006. Gross margin slipped to 19.5% from 20.3%.

Administaff Inc. (NYSE: ASF)
For the fourth quarter ended Dec. 31, 2007, compared with the same period in 2006.
Revenue: $402.1 million, +14.1%
Net income: $13.3 million, -0.4%

For the 2007 fiscal year ended Dec. 31, 2007, compared with the previous year.
Revenue: $1.57 billion, +13.0%
Net income: $47.5 million, +2.1%