• by Wayne Friedman , October 7, 2009

It's that time of year -- not the fall TV season but the usual fall TV season falloff.

New networks shows -- now with a couple of weeks' worth of data under their belts -- are settling in. Read that to mean lower numbers in some cases.

For example, CBS' "NCIS: Los Angeles" has trended down from its 4-plus ratings among 18-49 viewers to a 3.6 rating on Tuesday -- still a good number by many standards. Even the original "NCIS" fell 13% to a 4.2/12.

"The Good Wife," CBS' other new show on Tuesday, posted a 2.9 rating among 18-49 viewers, down 9% from the week before.

Overall, CBS still won the night -- with an average 3.6/10 among 18-49 viewers. But its margin of victory was smaller than a week ago.

ABC's venerable "Dancing with the Stars" shows signs of weakening -- now down to a 2.4 rating/6 share, its lowest numbers ever for a single show. On the flip side, Fox's dancing show, "So You Think You Can Dance?," moved up a bit, now at a 2.5/7.

While the 18-49 numbers are important here, one big thing to consider with the "Dance" shows is the overall viewers. "Stars" regularly pulls in more. On Tuesday, it averaged 11.7 million viewers more than double the 5.4 million for "Dance."

NBC stayed pretty much the same -- week-to-week overall. "The Biggest Loser" grabbed a steady 3.3/9 at 8 p.m. and an even better 3.9/11 at 9 p.m., actually beating "NCIS: Los Angeles" for the first time.

Looking for trends for NBC's "The Jay Leno Show" continues to be a tough task. After Monday's 1.5 rating/4 share among 18-49 viewers, the show moved up to a 2.1/6 on Tuesday. Analysts say the big ratings lead-in from "Loser" was a major contributor.

CW witnessed some positive news: "90201" earned a 1.2/3 and "Melrose Place" took a 0.9/2 among 18-49 viewers. This would be a slight rise for new show "Place" week-to-week, but flat versus its key women 18-34 demo at a 1.5 rating.

Among 18-49 averages for the night, NBC came in second after CBS with a 3.1/8; Fox was at a 2.8/8; ABC earned a 2.0/5; Univision came in at a 1.4/4; and CW finished with a 1.0/3. Among 18-34 viewers, Fox won the night with a 2.7/8. Last week, CBS was the winner in that category.