Fox wins night among 18-49 viewers

The May sweeps opened Thursday with CBS’ “The Big Bang Theory” the top-rated show among viewers 18-49 but with Fox scoring a primetime victory among the networks.

According to preliminary nationals from Nielsen, “Big Bang” (4.0 rating/13 share in 18-49, 12.5 million viewers overall) was tops at 8 p.m. and demonstrably stronger than a year ago, when it posted a 3.3/10 in the demo.

“American Idol” (3.9/12, 14.4 million), on the other hand, has dropped dramatically from where it was last year at this time (5.7/17), through it remains the night’s top program among total viewers.

Fox in fact won the hour over CBS, which had “Rules of Engagement” (2.5/7, 8.3 million) at 8:30 p.m. NBC was third in 18-49 with “Community” (1.4/4, 3.3 million) and a live-on-both-coasts episode of “30 Rock” (1.6/5, 3.5 million), followed by ABC’s “Missing” (1.3/4, 6.9 million) and the CW’s “The Vampire Diaries” (1.0/3, 2.2 million).

ABC surged to the top at 9 p.m. with “Grey’s Anatomy” (3.2/8, 9.3 million), which topped CBS’ “Person of Interest” (2.4/6, 12.5 million) in the demo if not total viewers. Thanks to “Touch” (1.9/5, 6.5 million), Fox was nearly even at 9 p.m. with NBC, which aired “The Office” (2.1/6, 4.1 million) and “Parks and Recreation” (1.6/4, 3.2 million). The CW offered “The Secret Circle” (0.5/1, 1.2 million).

At 10 p.m., CBS’ “The Mentalist” (2.1/6, 11.9 million) and ABC’s “Scandal” (2.1/6, 7.0 million) were even in the demo at 10 p.m., with NBC’s “Awake” (0.8/2, 2.2 million) trailing.

Preliminary 18-49 averages for the night: Fox 2.9/8, CBS 2.6/7, ABC 2.2/6, NBC 1.4/4, CW 0.8/2.

In total viewers: CBS 11.6 million, Fox 10.5 million, ABC 7.7 million, NBC 3.1 million, CW 1.7 million.

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