Automatic Data Processing Inc. reported a higher-than-expected quarterly profit as it processed more payrolls.

The company said the number of employees on its clients' payrolls rose 2.6 percent in the United States for the quarter ended Sept. 30 as measured on a same-store-sales basis.

Revenue from its employer services unit, which accounts for about 70 percent of overall business, rose 8 percent to $1.97 billion.

Net earnings from continuing operations rose to $328.6 million, or 68 cents per share, in the first quarter from $302.5 million, or 63 cents per share, a year earlier.

On an adjusted basis, the company earned 68 cents per share.

Total revenue rose about 8 percent to $2.84 billion.

Analysts had expected earnings of 66 cents per share on revenue of $2.81 billion, according to Thomson Reuters I/B/E/S.

ADP shares closed at $76.35 on the Nasdaq on Tuesday.