Big Bang Theory

The ratings keep getting bigger for The Big Bang Theory — and they keep getting smaller for American Idol.

The hit sitcom bested Idol outright for the first time in both viewership and the adults 18-to-49 demo Thursday, drawing 16.1 million and a 5.2, improving a tenth from last week. Idol averaged 15.4 million and a 4.4 (down 14 percent in the demo) for the hour. During the shows' 30-minute face-off, Idol snagged 14 million and a 4.0.

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But the number of biggest concern to Fox: Idol plummeted a massive 39 percent in the demo from its same telecast a year ago.

Overall, CBS and Fox tied for the night in the demo with a 3.2, but CBS won in terms of viewership. Though Rob (10.63 million, 3.0) and The Mentalist (13.2 million, 2.5) fell to series and season lows in the demo, Person of Interest (14.41 million) tied Grey's Anatomy (8.91 million) for the first time in that category with a 3.1.

8 p.m.
CBS:
The Big Bang Theory 16.1 million viewers (5.2 demo rating); Rob 10.63 million viewers (3.0)
ABC: Wipeout 5.0 million (1.5)
Fox: American Idol 15.4 million (4.4) [8-9 p.m.]
NBC: 30 Rock 3.71 million (1.5); Parks & Recreation 3.42 million (1.7)
CW: The Vampire Diaries (R) 1.29 million (0.5)

9 p.m.
CBS:
Person of Interest 14.41 million (3.1)
ABC: Grey's Anatomy 8.91 million (3.1)
Fox: The Finder 6.22 million (2.0)
NBC: The Office 4.98 million (2.6); Up All Night 3.45 million (1.8)
CW: Supernatural (R) .91 million (0.3)

10 p.m.
CBS:
The Mentalist 13.2 million (2.5)
ABC: Private Practice 6.41 million (2.2)
NBC: Grimm (R) 2.2 million (0.9)