Fast National ratings for Monday, March 22, 2010.

The latest season premiere of "Dancing with the Stars" delivered huge ratings to ABC, nearly "American Idol"-style ratings, giving "Castle" a big boost and helping the network dominate Monday night.
 
Among adults 18-49, ABC averaged a 5.4 rating, topping the 3.9 rating for the night's normal winner, CBS. FOX was third in the key demographic with a 2.2 rating, beating the 1.7 rating for NBC. The CW's 0.9 rating trailed.
 
Overall, ABC averaged an estimated 20.24 million viewers to go with a 12.7 rating/20 share. CBS' 6.8/11 was a distant second, still well in front of the 4.2/6 for FOX. NBC's 3.3/5 was fourth, beating the 1.3/2 for The CW.
 
ABC started the night in first with a 14.1/22 for "Dancing with the Stars," which also did a 5.8 demo rating. CBS' "How I Met Your Mother" and "Rules of Engagement" had a 5.3/8 and a 3.4 rating in the demo. NBC's "Chuck" had a 3.3/5 and a 1.9 demo rating, down in viewers, but steady from last week in the demo. FOX's "House" tied "Chuck" in the ratings, but was lower in viewers and the demo. In fifth, The CW's "Life Unexpected" had a 1.3/2, down very slightly from last week, but less than one might expect given the female-driven "Dancing" focus.
 
"Dancing with the Stars" improved to a 15.6/23 in its second hour, drawing more than 25.1 million viewers and a 6.9 demo rating for ABC. That took a bite out of CBS' "Two and a Half Men" and "The Big Bang Theory," which did an 8.2/12 and a 5.1 rating in the demo. FOX's "24" had a 5.2/8 for third. NBC's "Trauma" was a distant fourth with a 2.7/4. The CW's "Gossip Girl" held most of its lead-in.
 
Note that the "Dancing with the Stars" premiere in September averaged just over 17.5 million viewers and a 4.1 demo rating, prompting industry observers to wonder if the show had peaked. Hmmm... To what do we attribute the bump? Chad Ochocinco? Buzz Aldrin? Were viewers just excited to get rid of Samantha Harris?
 
The "Dancing" boost helped "Castle" to an 8.4/14 and a 3.6 demo rating, both enough to win the 10 p.m. hour. CBS' "CSI: Miami" had an extra-low 6.8/12 and a 3.2 rating in the demo. NBC's "Law & Order" was third for the hour.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.