When Jay Leno departed "The Tonight Show" in 2014, he had 14.6 million viewers, according to Nielsen
'Long way back from Johnny Carson's farewell show in 1992 which drew 50 million viewers
David Letterman's final appearance as host of "The Late Show" averaged 13.76 million viewers, the CBS program's best ratings performance since February 1994..
That's more than four times the 2.8 million viewers "The Late Show" has averaged for the 2014-15 season. The Wednesday telecast was the fourth most-watched "Late Show" episode since the show premiered in 1993.
Letterman's finale on Wednesday averaged a 3.1 rating among 18 to 49 year olds, the group most coveted by advertisers. That number is the highest since Dec. 1, 2005, when Letterman had Oprah Winfrey as a guest. A total of 13.5 million watched that episode.
Only three "Late Show" telecasts have had larger audiences than the Letterman farewell. The largest was on February 25, 1994 following CBS coverage of the Winter Olympics in Lillehammer.
Letterman's debut on CBS on August 30, 1993, was the second most watched episode, with 15.1 million viewers.