• by Wayne Friedman , December 9, 2009

For this season so far, cable TV's share of viewing climbed at the expense of broadcast in program ratings. But cable's picture isn't entirely positive when looking at commercial rating data.

Ad-supported cable TV viewing has now grown to a 60.6 share to broadcast networks' 32.1 share when looking at program ratings. The same trend exists for 18-49 viewing -- the most desired demographic group for TV advertisers. Ad-supported cable is now up to a 50.7 share versus broadcast's 27.3 number.

This data comes from Turner Research and Nielsen Media Research in looking at live program-plus-seven-day data through November 22 and live program-plus-same-day numbers from November 23 through December 6, 2009.

Both overall viewership and 18-49 viewing improved for cable and declined for broadcast networks versus a year ago. Last year, overall viewing share for cable was at 59.2; for broadcast, it was at 32.7. For 18-49, 2008's numbers stood at 49.0 for cable, 28.1 for broadcast.

According to Turner, one key area comes at the 10 p.m. time period, where NBC made a dramatic move in placing "The Jay Leno Show" in the time slot five nights a week. As expected, the show has been posting numbers generally below what its dramas have done a year earlier.

Turner says NBC is down an average of 1.3 rating program rating points among 18-49 viewers, with the other broadcast networks off 1.3 ratings on average. At the same time, ad-supported cable has grown 1.6 average ratings among 18-49 viewers in the 10 p.m. to 11 p.m. time period.

But not all ad-supported cable networks move in a lock-step upward trend.

In looking at just prime-time C3 ratings -- commercial ratings plus three days of DVR playback -- ad-supported cable is down 4% among 18-49 viewers, and down 7% among 25-54 viewers through November 16, according to data released by CBS Vision's David Poltrack at the UBS Media Conference on Wednesday.

Poltrack went on to note that seven of the ad-supported cable networks grew year-to-year among their C3 adults 18-49 viewers, while 12 networks declined and 19 went unchanged. Six cable networks' 25-54 numbers were lower versus a year ago, 11 were down versus a year ago, and 21 were unchanged.

The broadcast networks have been down as well in the season-to-date C3 ratings: 6% lower among 18-49 viewers, with a 6% decline among 25-54 viewers.

Broadcast network did a bit better than cable in stemming the erosion when it came to overall viewership, with the broadcasters losing 2% and cable networks down 6%.