The Kentucky Derby broadcast on NBC on Saturday posted a 9.1 overnight rating and a 21 share, according to the television network, with both figures representing significant declines from last year. The 9.1 overnight rating was a 13 percent decline from the 10.5 rating posted last year, while the 21 share was an 8.7 percent decline from the 23 share posted last year. While the overnight rating is a numerical measure of the number of people watching a broadcast, share is a measure of the percentage of televisions in use that are tuned into a broadcast. The broadcast on NBC ran from 2:30 to 7:15 p.m. Eastern. The overnight figures are typically calculated for the portion of the broadcast starting at 5:00 through its conclusion. NBC said the rating and share peaked at the time of the Derby at 10.9 and 25. The Derby broadcast this year went up against an NBA playoff game that started at 5:00 featuring the Boston Celtics and Philadelphia 76ers. NBC said the broadcast figures this year were “comparable” to the last time the Derby broadcast went head-to-head against an NBA game, in 2016, when the rating was a 9.4 and the share was 21. NBC said the 9.1 rating was the best for any Saturday television broadcast since a Winter Olympics broadcast Feb. 17. The ratings declines occurred despite record-high wagering figures for both the Derby and the entire Derby card.