Fast National ratings for Thursday, May 5, 2011.
 
A busy May Sweeps Thursday saw continued dropping for CBS' tired "CSI," a post-Carell dip for "The Office" and improved performances from "American Idol" and "Bones," which led FOX to comfortable ratings wins.
 
Among adults 18-49, FOX averaged a 4.7 rating for the night, easily tops in the key demographic. CBS was a distant second with a 2.5 rating, with ABC's 2.4 rating close behind. NBC's 2.0 rating finished fourth for the night, doubling up the 1.0 rating for The CW.
 
Overall, FOX averaged an estimated 15.95 million viewers and a 9.3 rating/15 share. CBS was second with a 7.0/11 and 11.025 million viewers, far ahead of the 4.9/8 and 7.185 million viewers for ABC. NBC's 2.6/4 and 4.22 million viewers held off the 2.3 million viewers and 1.5/2 for The CW.
 
8 p.m. - "American Idol" controlled the 8 p.m. hour with 20.81 million viewers and a 6.1 rating among adults 18-49, (up from 19 million and a 5.5 demo rating last week). CBS was second with "The Big Bang Theory" (declining to 10.26 million viewers and a 3.1 demo rating) and "Rules of Engagement" (7.7 million viewers and a 2.2 demo rating). ABC's "Wipeout" was a distant third with nearly 4.8 million viewers and a 1.4 demo rating. NBC's "Community" (3.46 million viewers and a 1.4 demo rating) and a repeat of "The Office" (2.7 million and a 1.1 demo rating) were fourth. The CW was fifth with 2.67 million viewers and a 1.2 demo rating for "The Vampire Diaries," which beat NBC in the 8:30 half-hour.
 
9 p.m. - FOX's "Bones" won the 9 p.m. hour overall with 11.09 million viewers and finished a close second in the key demo with a 3.3 rating, both up from last week. CBS' "CSI: Crime Scene Investigation" was second with 10.46 million viewers and saw its demo rating fall to a 2.2 rating. "Grey's Anatomy" finished third overall with 9.86 million viewers for ABC, but at least won the hour in the key demo with a 3.5 rating. NBC's "The Office" (6.76 million and a 3.5 demo) was down from last week's heavily hyped Steve Carell exit, but still up from the episode two weeks ago, while "Parks & Recreation" (5.07 million and 2.6 demo rating) was steady. On The CW, "Nikita" averaged 1.93 million viewers and a 0.8 demo rating for fifth.
 
10 p.m. - CBS closed primetime in first with the 13.635 million viewers for "The Mentalist," which also won the hour with a 2.6 demo rating. ABC's "Private Practice" averaged 6.89 million viewers and a 2.3 demo rating for second. NBC's "30 Rock" (4.21 million and a 2.1 demo) and "Outsourced" (3.145 million and a 1.5 demo) trailed.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.