Fast National ratings for Thursday, April 16, 2015.

"The Big Bang Theory" ticked up for the second week in a row and did its duty in helping CBS dominate Thursday overall and pull off a slim key demo victory over ABC, which got a bump for "American Crime."

Among other variable notables, "Backstrom" ticked down a little, as did "The Vampire Diaries." "Scandal" and "Mom" were both up.

Let's get to the numbers...

Among adults 18-49, CBS averaged a 2.1 rating among adults 18-49 for Thursday night, topping the 1.9 rating for ABC in the key demographic. There was a big drop to FOX's 0.9 key demo rating, NBC's 0.8 key demo rating and the 0.5 key demo rating for The CW on the night.

Overall, CBS averaged an estimated 9.56 million viewers and a 5.9 rating/10 share for Thursday primetime. ABC was a distant second with 6.63 million viewers and a 4.5/8. NBC's 2.8/5 and 4.21 million viewers edged out FOX's 2.5/4 and 4.06 million viewers. And The CW averaged 1.17 million viewers and a 0.8/1 for Thursday night.

8 p.m. - CBS started primetime in first with "The Big Bang Theory" (14.495 million and a 3.7 key demo) and "The Odd Couple" (9.765 million and a 2.2 key demo). ABC's "Grey's Anatomy" was second with 7.575 million viewers and a 2.1  rating among adults 18-49. FOX's new "Bones" averaged 4.75 million viewers and a 1.0 key demo rating, topping the 3.85 million viewers and 0.7 key demo rating for NBC's "Law & Order: Special Victims Unit" repeat. The CW's "The Vampire Diaries" averaged only 1.34 million viewers and a 0.6 key demo rating.

9 p.m. - CBS won the 9 p.m. hour overall and finished second in the key demo with "Mom" (9.66 million and a 2.2 key demo) and a "Big Bang Theory" repeat (8.58 million and a 1.9 key demo). ABC's "Scandal" was second with 7.86 million viewers and won the hour with a 2.4 rating among adults 18-49. FOX's "Backstrom" averaged 3.36 million viewers to edge out the 3.33 million viewers for NBC's "Blacklist" repeat, while both dramas did a 0.7 key demo rating. The CW's "Reign" averaged 999,000 viewers and a 0.4 key demo rating.

10 p.m. - "Elementary" closed primetime in first with 7.43 million viewers for CBS, also winning the hour with a 1.4 rating among adults 18-49. NBC's "Dateline" averaged 5.44 million viewers to beat the 4.44 million viewers for ABC's "American Crime," but both networks had a 1.1 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.

A long-time member of the TCA Board and a longer-time blogger of "American Idol," Dan Fienberg writes about TV, except for when he writes about movies or sometimes writes about the Red Sox. But never music. He would sound stupid talking about music.