LOS ANGELES (AP) _ Fox Broadcasting Co. on Wednesday announced its highest February sweeps ratings in the network's 6-year-old history.

Fox showed a 23 percent increase from last year in its average rating for the sweeps period running from Feb. 6 through Wednesday, according to figures supplied by Fox.

The network finished behind the top three networks, but managed an 8.7 average rating although is has fewer stations and programs only four nights a week.

CBS' Winter Olympics coverage helped it finish first with a 16.8 average rating. NBC was second with a 13 rating and ABC was third with 11.9, according to Fox figures compiled from the A.C. Nielsen Co.

The February sweeps are one of four yearly ratings periods used by network stations to help set advertising rates. Each ratings point represents 921,000 homes.

Fox's Andy Fessel, senior vice president of research and marketing, attributed the network's improved February standings to increased viewership among younger viewers.

Teen favorites, such as ''The Simpsons'' and ''Beverly Hills, 90210'' drew good ratings against Olympic coverage, he said.