Fast National ratings for Thursday, May 10, 2012.
 
"American Idol" was flat week-to-week and lifted FOX to a win on Thursday night among young viewers, while the season finale of "The Big Bang Theory," despite a week-to-week drop, led CBS' overall win.
 
Among other ratings highlights, finales for "The Vampire Diaries," "The Office" and "Parks and Recreation" were steady, a pre-finale "Grey's Anatomy" delivered its biggest demos in months and NBC's "Awake" stopped its steady decline (at least for a week).
 
Among adults 18-49, FOX averaged a 2.9 rating for the night, edging out CBS' 2.8 rating in the key demographic. ABC was third with a 2.2 rating, with NBC averaging a 1.4 key demo rating. The CW averaged a 0.8 key demo rating for Thursday night.
 
Overall, though, CBS averaged an estimated 12.06 million viewers and a 7.5 rating/12 share, beating FOX's 6.7/11 and 11.02 million viewers for Thursday primetime. ABC was a distant third with a 5.1/8 and 7.47 million viewers, still far ahead of NBC's 2.0/3 and 3.16 million viewers. The CW averaged a 1.2/2 and 1.86 million viewers.
 
[For Thursday night, Univision averaged 3.58 million viewers and a 1.4 rating among adults 18-49.]

8 p.m. - FOX started Thursday primetime in first with nearly 15.1 million viewers and a 3.9 rating among adults 18-49. CBS' "The Big Bang Theory" (13.3 million and a 4.2 key demo) beat "Idol" for its half-hour, but "Rules of Engagement" (8.95 million and a 2.7 key demo) did not. ABC's "Missing" averaged 6.36 million viewers for third overall and came in tied for fourth in the key demo with a 1.1 rating. NBC was fourth overall and third in the demo with "Community" (3.12 million and a 1.4 key demo rating) and "30 Rock" (2.95 million and a 1.5 key demo). The CW's season finale of "The Vampire Diaries" averaged 2.49 million viewers and a 1.1 key demo rating.
 
9 p.m. - CBS moved into first overall in the 9 p.m. hour with the 12.685 million viewers for "Person of Interest," which finished second with a 2.6 rating among adults 18-49. ABC's "Grey's Anatomy" was second with 9.56 million viewers and won the hour with a 3.4 key demo rating. FOX's "Touch" averaged 6.94 million viewers and a 2.0 key demo rating. NBC was fourth overall and tied for third in the key demo with finales of "The Office" (4.44 million viewers and a 2.2 key demo) and "Parks and Recreation" (3.46 million and a 1.7 key demo). The CW's "Secret Circle" finale averaged 1.24 million viewers and a 0.5 key demo rating, as it now goes to wait on the netlet's bubble.
 
10 p.m. - "The Mentalist" averaged 12.42 million viewers and a 2.4 rating among adults 18-49 to win the 10 p.m. hour for CBS. ABC's "Scandal" averaged 6.48 million viewers and a 2.0 key demo rating, slightly down from last week. NBC's "Awake" was slightly up with nearly 2.5 million viewers and a 0.9 key demo rating. 
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.