Yes, Folks, a Year Later, Dave’s Still the Top Guy : Television: Letterman’s appeal on ‘Late Show’ spans generations and genders, giving a boost to CBS in particular and late-night TV in general.

David Letterman’s CBS series marks its first anniversary on Tuesday, and the numbers pretty much tell the story.

In head-to-head competition with Jay Leno, who beat him out as Johnny Carson’s successor on NBC’s “Tonight Show,� Letterman has won all 51 weeks in the ratings thus far. (Ratings for this week aren’t available yet.)

“We expect to win all 52 weeks,� says co-executive producer Peter Lassally, who left “Tonight� to help guide CBS’ “Late Show With David Letterman.� “Believe me, we did not expect that.�

Nor did CBS or NBC or sponsors or the top TV experts, who pretty much hemmed and hawed when it came to putting themselves out on a limb in judging who was most likely to succeed in inheriting Carson’s crown in the new late-night race.

What it all proves is that your guess is probably as good as some fancily titled six- or seven-figure TV wizard when it comes to judging what will or won’t triumph on the screen.

So much has been stated and restated about Letterman’s remarkable year that audience judgment tends to be overlooked. You’ll remember that Letterman’s previous series, a late-late entry following Carson on NBC, developed a cultish image of appealing chiefly to the young. And female viewers were supposedly not too fond of him.

But according to CBS research chief David Poltrack, Letterman’s current series cuts across the board in the ratings. About one-third of the audience is 18 to 34 years old, another third is 35 to 49 and the other third is 50-plus, says Poltrack. In addition, he says, 55% of the “Late Show� audience is women, 45% men.

The numbers also tell the story in the advertising rates the Letterman show now commands.

When it made its debut as a distinct underdog on Aug. 30, 1993, with only about 67% of CBS stations carrying the series in its regular 11:35 p.m. slot, the network was guaranteeing sponsors just a 4.1 rating--with 30-second commercials offered at about $25,000, according to Madison Avenue sources. When the show took off like a rocket, the remaining scattered commercial spots were raised to about $40,000 each, the advertising sources say.

Instead of the 4.1, Letterman has averaged a 5.8 and 18% of the audience for the full year, outdistancing its competitors--ABC’s “Nightline,� which drew a 4.9 and 14% audience share, and “Tonight,� which scored a 4.4 and a 13 share. (Each rating point represents 942,000 homes.)

As a result, advertising and network sources say, much of the upfront sales for 30-second spots on the Letterman show for the new season run between roughly $40,000 and $50,000, with other late and “scatter� sponsor purchases running as high as $60,000, perhaps a little more on occasion.

Letterman’s three-year deal with CBS reportedly brings his production company, Worldwide Pants Inc., $42 million. Part of the deal calls for him to produce another show that follows his own, and late-night veteran Tom Snyder has been signed for that series, which is scheduled to begin in December.

Although Letterman is now middle-aged--he’s 47--advertising executive Joel Segal of the McCann-Erickson agency says the series appeals to sponsors because “it’s attention-getting� and skews young for CBS, which has traditionally attracted older viewers than its competitors.

Letterman’s effect on CBS’ ratings and income pops out when compared to the action shows he replaced. Those shows averaged a 2.9 rating and 10% audience share, selling 30-second commercials for about $15,000 apiece, Poltrack says.

“So it’s a 100% ratings increase over the full year, a doubling,� he says. “But what’s interesting is that ‘Tonight’ and ‘Nightline’ haven’t gone down much at all, yet overall viewing in the late-night period is up 20%. So the Letterman show has been good for all of late-night television, not just CBS.�

Letterman--whose ratings are nearly one point higher in homes with $60,000-plus income and household heads with four or more years of college--draws an average audience of 7.2 million viewers, Poltrack says. This, he says, compares with an average 6 million for “Nightline� and 5.3 million for “Tonight.�

Lassally says there is potential for more growth because the Letterman show still is cleared at 11:35 p.m. by only about 90% of CBS stations.

The Letterman contingent, though, has a lot riding on Snyder’s upcoming series as its first outside production at CBS.

Says Poltrack: “One of the things ABC has going for it right now is ‘Nightline.’ When something’s breaking or happening, they have that extra level of coverage. What we will have in Snyder is not the same as ‘Nightline’ but another forum. It will be topical and have hot personalities.�

Says Snyder: “Certainly if there’s something that warrants attention or news, we would do it. In no way are we CBS News, but we could at least maintain some kind of presence.�

Snyder, whose current CNBC cable talk series propelled him back into the TV spotlight, says the target date for his CBS show is Dec. 12, “but it may be that or Jan. 12. It all depends on them to get ready for us. That’s all being handled by Worldwide Pants.�

Can the 58-year-old Snyder hold a reasonable portion of the Letterman audience? Cracks Poltrack: “As Generation X says, he has attitude.�

Looking to his post-Letterman slot, Snyder says: “My show is not comedy-driven, so we’ll complement each other. Obviously, while the time slot is not Valhalla, it’s important to CBS. And I’m complimented to be following the Letterman show.� Addressing the age question, he adds: “It’s understandable. But people will watch if it’s good.�

Is the Letterman show planning something special to celebrate its first anniversary?

“On Monday,� says Lassally, “we will sit down and figure it out. It will not be ignored. Maybe we’ll show a few highlights. We are known for pulling something together in 24 hours.�