text: Carson is the longest-serving host to date, although he is not the host with the most episodes. The Tonight Show Starring Johnny Carson aired for 30 seasons between October 1962 and May 1992. Leno has the record of having hosted the greatest number of total televised episodes. Leno's record is due to the fact that, unlike Carson (who only produced new shows three days a week starting in the 1980s), Leno never used guest hosts on The Tonight Show with Jay Leno (except Katie Couric, once) and produced new shows five days a week; Leno himself was also Carson's primary guest host for the last five years of Carson's tenure, adding even more episodes to his credit. Leaving out Leno's five years as permanent guest host, Leno hosted 119 more episodes as full-time host than Carson. During Carson's first four years, the show ran for 105 minutes and then was reduced to ninety minutes in early 1967 when Carson stopped appearing for the first 15 minutes because most affiliates were carrying their local news during that time slot as they expanded to half an hour. During Carson's 1980 contract negotiations, the show was shortened to sixty minutes beginning that September, where it has remained since. NBC also broadcast The Best of Carson which were repeats of some of Carson's popular older albeit usually recent shows. Prior to the debut of Saturday Night Live in October 1975, NBC aired The Best of Carson on Saturday nights at 11:30 pm.