Melville, N.Y. Olsten Corp.'s net earnings for the third quarter ended Oct. 3 jumped 23 percent to $13.8 million, or 17 cents a diluted share, compared with $11.2 million, or 14 cents a diluted share, a year ago. Revenue for the quarter was $1.26 billion, an 8 percent increase over the $1.17 billion reported in the same quarter of 1998.

The company's health services division, which Olsten plans to spin off by year's end, recorded third-quarter revenues of $377 million, compared to $321 million the prior year.

Olsten also restated its consolidated financial statements for fiscal 1998, ended Jan. 3, 1999, as well as for the first quarter of fiscal 1999. It reported a loss of $35.5 million, or 44 cents per diluted share, for fiscal 1998. It had originally reported net income of $4.4 million, or 5 cents per diluted share. For the quarter ended April 4, 1999, the company reported a loss of $22.4 million, or 28 cents per diluted share, as compared to its previous report of a net loss of $62.3 million, or 77 cents per diluted share.-S.H.