Fast National ratings for Thursday, February 16, 2012.
 
Yet another two-hour "American Idol" helped FOX rule Thursday night in all key measures, but after a couple weeks of steady performance or even gains, the talent show took a big drop. Then again, it was another night on which nearly everything was down, especially in the "Idol"-impacted 9 p.m. hour.
 
Among adults 18-49, FOX averaged a 5.0 rating, way ahead of CBS' 3.3 rating in the key demographic. ABC was third with a 2.4 rating, followed by NBC's 1.4 rating and the 1.0 rating for The CW.
 
Overall, FOX averaged an estimated 16.495 million viewers to go with a 9.7 rating/15 share. CBS was second with an 8.1/13 and 13.355 million viewers. There was a big drop to ABC's 4.4/7 and 6.78 million viewers and another big drop to NBC's 2.0/3 and 3.08 million viewers. The drop to The CW's 1.5/2 and 2.31 million viewers wasn't nearly so big.
 
[On a strong night, driven by Premio Lo Nuestro 2012, Univision averaged 5.08 million viewers and a 2.1 rating among adults 18-49, comfortably beating both The CW and NBC.]
 
8 p.m. - "American Idol" drew 16.56 million viewers and a 5.0 rating among adults 18-49 to win the totality of the 8 p.m. hour. CBS' "The Big Bang Theory" (15.52 million and a 5.0 key demo rating) actually beat "Idol" overall and in the key demo for its half-hour, but "Rob" (10.905 million and a 3.2 key demo) did not, despite consistent retention. ABC's "Wipeout" averaged 5.13 million viewers for third overall and a 1.5 key demo rating for fourth. NBC was fourth overall and third in the demo with "30 Rock" (3.6 million and a 1.4 key demo) and "Parks and Recreation" (3.51 million and, up a hair, a 1.7 key demo). The CW's "The Vampire Diaries" averaged 2.855 million viewers and a 1.3 key demo rating.
 
9 p.m. - Unlike Wednesday, when the show's second hour took a big leap, "American Idol" averaged 16.425 million viewers and a 5.0 rating among adults 18-49 to win the 9 p.m. hour. "Idol" took a big bite out of CBS' "Person of Interest," which dropped to a still-strong 13.25 million viewers after consecutive weeks around 15 million, also falling to a 2.9 key demo rating in third. ABC's "Grey's Anatomy" also shed roughly 2 million viewers, drawing only 8.13 million viewers and finishing second with a 3.1 key demo rating. NBC's "The Office" (4.34 million and a 2.2 key demo) and "Up All Night" (3.01 million viewers and a 1.5 key demo) both suffered predictable declines. Oddly, "Idol" had no real impact on "The Secret Circle," which still drew 1.76 million viewers and a 0.8 key demo rating.

10 p.m. - CBS moved into first for the 10 p.m. hour with 13.61 million viewers and a 2.8 key demo rating for "The Mentalist." ABC's "Grey's Anatomy"-boosted "Private Practice" was up week-to-week with 7.09 million viewers and a 2.6 key demo rating. NBC's repeat of "Grimm" drew only 2.03 million viewers and a 0.7 key 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.