'SNL 40′: Inside the NBC Sketch Show's Roaring Ratings Highs and Looming Lows

NBC's "Saturday Night Live" is officially over-the-hill — so what do you get the sketch comedy show that has everything for its 40th birthday? Based on TheWrap's study of the NBC staple's historical Nielsen numbers, we're willing to bet that Lorne Michaels would gladly take better ratings.

"SNL" hit its high note from an eyeball-measuring perspective during the 1978-1979 season — the sketch comedy show's fifth run — which averaged a 13.5 household rating. Today, the show gets roughly one-third of that gaudy number, even counting the time-shifted viewing that didn't exist for about 30 years of its existence.

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The early seasons' "Not Ready for Primetime Players" grew the show's ratings steadily through each of the five years ending the 1970's, but experienced a big drop when the '80s hit and the gang broke up. By the generally accepted death of disco, Chevy Chase was long gone, and Dan Aykroyd and John Belushi were New York City memories. Each of the three key players departed for the greener pastures of Hollywood.

They wouldn't be the last to leave in a Manifest Destiny-esque trip out west to try and turn TV silver into Los Angeles gold: Bill Murray, Jane Curtin, Garrett Morris, Laraine Newman, Gilda Radner, Tom Davis, Al Franken and many other key members departed in 1980, crippling the program temporarily. Since then, the show's decline has been steady, though with some ebbs and flows along the way.

That said, it is important to note that changing viewing habits overall play a role in the general decline of TV ratings throughout the decade, and "SNL" is no exception. Another piece of TheWrap's below chart that bears explanation: Numbers from the key 18-49 demographic were not available until the 1987-1988 season. These won't be the last qualifiers.

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According to Nielsen's "most current" metric, which includes Live + 7 Day numbers where available, as you read this, "Saturday Night Live" is experiencing its lowest-rated season ever in the main demo. And it's not that close either, with the season-to-date 2.7 average falling a full three-tenths of a ratings point beneath 2006-2007's and 2007-2008's 3.0 averages.

That said, in the household "most current" rating, the present-time 40th season actually matches 2006-2007 — each with a 4.6 — and 2007-2008 would be the lowest-rated year, averaging a 4.5. Plus, the season isn't over yet, and theoretically "SNL 40″ could spark a ratings resurgence of sorts.

But here's another asterisk that comes from the mid-2000's: Nielsen didn't start counting time-shifted viewing until Dec. 26, 2005, so there was no such thing as Live + 7 Day or "most current" until then, skewing results around that time of early DVR adoption.

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Let's rewind a bit again for another highlight: For those who remember the early-mid '90s as "SNL's" "Golden Years," the ratings sort of reflect that. For the years available, 1992-1993 hit a high in the available key demo, with a 7.1 rating. That year also had the most average viewers from the data set, with 12.7 million. These were the years of Chris Rock, Dana Carvey, Kevin Nealon, Phil Hartman, Chris Farley, David Spade, Adam Sandler and Tim Meadows, among others.

But enough words — look at the graphic below, which only counts original episodes: