David Letterman’s Departure Will Mark Irreparable ‘Late Shift’ For TV

Analysis: TV's last connection to the days of Johnny Carson will break, and the aspirations of latenight hosts will diminish

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When David Letterman steps down from his ’round-midnight perch sometime next year, TV will feel like it has been been a victim of one of the pranks that brought him so much notice when he was starting out on NBC’s “Late Night.” The act is likely to be the equivalent of being thrown off a five-story tower or squashed by a steamroller.

Why? Because when Letterman goes, latenight TV loses the one host who remembered when a single wee-hours personality held the entire nation in thrall. Letterman is TV’s last link to the Johnny Carson era, and the only one who still made an effort once in a while to talk to the nation – not just that sliver of it that represented a particular demographic niche.

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Look, it’s no secret latenight viewership is on the wane. More folks seem to pass along clips from the shows on YouTube than watch an episode live. Consider that in 2010, Jay Leno’s “Tonight” had an average of nearly 3.8 million viewers, according to Nielsen. In 2013, it had an average of 3.5 million. Jon Stewart’s “Daily Show” on Comedy Central had 1.5 million in 2010; in 2013, 1.45 million. TBS'”Conan” had an average of 1.65 million in 2010; in 2013, the average is 831,000, Nielsen said.

Letterman has been victim to the same forces affecting his rivals: a splintering audience that has two handfuls of latenight choices and no real impetus to watch any of it live. In 2010, CBS'”Late Show” captured an average of 3.4 million viewers. In 2013, the number slipped to a little less than 2.8 million (ABC’s Jimmy Kimmel proves the exception to the rule, but his show moved to an earlier roost last year, thwarting an apples-to-apples comparison).

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But that hasn’t kept Dave from acting as if the show reached everyone. It was Letterman, after all – not Jay Leno, who had the bigger viewership – who was the first latenight host to address the terrorist attacks of September 11, 2001, and tried to cajole couch potatoes to get back into a routine. It has been Letterman who refuses to stick to a set of talking points when chatting up the celebrities on his couch. And it has been Letterman who has admitted his own failings to his audience, as he did in 2009 when acknowledging a series of affairs he had been extorted into disclosing. He has even been willing to throw a few barbs at CBS CEO Leslie Moonves.

No matter who CBS chooses to put on in the timeslot next year, chances are viewership will dip and decline as it does elsewhere on the dial. These days, the hosts don’t even aspire to be King of Late Night. “I think Johnny Carson was the last King of Late Night,” Jimmy Kimmel told me in 2013 when I interviewed him for Advertising Age. “I hope to have a narrow edge on everyone else. That’s really all you can hope for.”

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Letterman comes from a time when one could hope for more. While modern viewers will flock to whichever latenight host most appeals to their particular age and gender, older ones will recall a time when the guy delivering jokes after the 11 p.m. news hoped to talk to everyone.