NBC, which paid a reported $51.5 million to telecast the Triple Crown for five years and end a 26-year run for ABC, saw a 26% increase in the overnight ratings for Saturday's Kentucky Derby. In figures compiled by the A.C. Nielsen Co., the Derby garnered an 8.3 rating in 51 television markets nationwide and a 20% share. That's up from the 6.6 rating and 17 share the Derby received in 2000 on ABC.This year's overnight was the highest since a 9.5 rating in 1992. Each rating point represents approximately one million homes, and market share is the percentage of televisions in use tuned in to a specific program.The telecast, scheduled for 90 minutes between 5-6:30 p.m. EDT, ran over by 13 minutes because of a claim of foul by the rider of runner-up Invisible Ink against the winner (the foul claim was dismissed by stewards). Viewership reached a peak of 11.3 ratings points between 6-6:30 p.m., the half-hour slot that included the running of the race.Ratings were expected to increase under NBC, chiefly because NBC had televised NBA playoff games in competition with the Derby when it was on ABC. This year, the Derby served as a lead-in to an NBA playoff game between Dallas and San Antonio. Interestingly, that game received a 33% ratings increase over last year's corresponding game between Philadelphia and Indiana.Louisville, home city for the Derby, measured a 65% market share for the Derby telecast. Final ratings are expected on Thursday.