And the No. 1 reason late-night will feel a lot more lonely ...
David Letterman, 66, announced Thursday that he is retiring after more than three decades of making people laugh after their bedtimes.
The funnyman, who began in 1982 on Late Night with David Letterman on NBC before moving to the Late Show with David Letterman on CBS, told the audience at Thursday's taping that he will leave next year.
He said he broke the news earlier to CBS CEO Leslie Moonves. "I said, 'Leslie, it's been great, you've been great, and the network has been great, but I'm retiring.'"
Added Letterman: "I just want to reiterate my thanks for the support from the network, all of the people who have worked here, all of the people in the theater, all the people on the staff, everybody at home, thank you very much. We don't have the timetable for this precisely down – I think it will be at least a year or so, but sometime in the not too distant future, 2015 for the love of God."
The host kicked off Thursday's taping with his normal opening monologue and then sat at his desk, talking about how people are always asking him how long he will do the show. He joked that it stopped being fun, but went on to do 10 more years.
Letterman, with his signature Top 10 lists, jumped to CBS in 1993, after former network NBC handed Johnny Carson's Tonight Show hosting torch over to Jay Leno instead of Letterman, who had expected to receive it.
This sparked ongoing rumors of a feud between the two hosts. Leno beat Letterman into retirement, stepping down for replacement Jimmy Fallon in February.
"For 21 years, David Letterman has graced our network's air in late night with wit, gravitas and brilliance, unique in the history of our medium," Moonves said in a statement on Thursday. "During that time, Dave has given television audiences thousands of hours of comedic entertainment, the sharpest interviews in late night, and brilliant moments of candor and perspective around national events."
Added Moonves: "He's also managed to keep many celebrities, politicians and executives on their toes – including me. There is only one David Letterman. His greatness will always be remembered here, and he will certainly sit among the pantheon of this business."
Reporting by JANINE RUBENSTEIN and EMMA TYLER