Fast National ratings for Monday, April 13, 2009.

Monday night continues to offer a topsy-turvy ratings world, with ABC dominating in total viewers with "Dancing with the Stars," but the normally more mature CBS winning in the key 18-49 demographic.

CBS did a 4.1 rating in the 18-49 demo, nipping the 4.0 rating for FOX in the all-important age group. ABC was third with a 3.4 rating, beating the 2.7 rating for NBC. The CW's 0.4 rating trailed.

Overall, though, ABC won the night easily, averaging an estimated 13.87 million viewers to go with a 9.0 rating/14 share. CBS was comfortably back in second with a 7.4/12, followed by the 6.9/10 for FOX. NBC's 4.2/7 took fourth, leaving The CW in last with a 0.7/1.

ABC started the night in first with an 11.9/18 for "Dancing with the Stars." FOX's "House" was second with a 7.2/11, while CBS' "Big Bang Theory" and "How I Met Your Mother" averaged a 5.9/9 between them. NBC's "Chuck" had a 3.7/6 for fourth (and a slightly-higher-than-normal 2.3 rating in the 18-49 demo). The CW's "Gossip Girl" repeat trailed.

At 9 p.m. ABC won with "Dancing with the Stars" (13.0/19) and "Surviving Suburbia" (6.9/10). CBS' "Two and a Half Men" and "Rules of Engagement" were second and won the hour in the 18-49 demo. FOX's "24" had a 6.5/10 for the hour, far in front of the 4.1/6 for NBC's "Heroes." The CW was last with a "One Tree Hill" repeat.

CBS moved into first at 10 p.m. with an 8.5/14 for "CSI: NY." ABC's "Castle" was second with a 5.1/8, nipping NBC's "Medium," though "Medium" held second in the 18-49 demo.

All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.