Fast National ratings for Monday, December 14, 2009.
 
The premiere of NBC's limited run singing special "The Sing Off" lost viewers at every half-hour, but still delivered a larger audience than "Heroes" and "Trauma." That isn't saying much, though, as CBS dominated Monday night in all key measures, thanks largely to "Two and a Half Men" and "The Big Bang Theory."
 
Among adults 18-49, CBS won the night with a 4.4 rating, far ahead of FOX's 2.2 rating. NBC's 2.0 rating and the 1.2 rating for ABC followed. The CW was fifth in the coveted demographic with a 0.6 rating.
 
Overall, CBS averaged an estimated 13.26 million viewers to go with an 8.1 rating/13 share. FOX was a distant second with a 4.1/6, followed by the 3.8/6 for NBC and ABC's 3.6/6. The CW trailed with a 0.9/1.
 
In the 8 p.m. hour, CBS got a 6.0/9 for "How I Met Your Mother" and "Accidentally on Purpose," way up from last week, also winning the key demo with a 3.6 rating. NBC's "The Sing Off" was second with a 4.5/7. FOX was third with a repeat of "House." ABC's Jennifer Hudson special did only a 3.9/6 overall and a 1.2 demo rating. The CW started its full-week "Vampire Diaries" marathon with a 1.0/2.
 
In the 9 p.m. hour, "Two and a Half Men" and "Big Bang Theory" averaged a 9.6/14 and a 5.4 rating in the demo. FOX moved up to second with the midseason finale of "Lie To Me," which did a 4.0/6. NBC's "The Sing Off" and ABC's "Find My Family" both did a 3.8/6, though NBC had the advantage in viewers and the demo. The CW was fifth with "The Vampire Diaries."
 
CBS stayed in first at 10 p.m. with an 8.9/15 for "CSI: Miami," which also did a 4.1 rating in the demo. NBC's "The Jay Leno Show" was second with a 3.1/5, beating ABC's "Castle" repeat.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.