Fast National ratings for Tuesday, October 23, 2012.
 
"Parenthood" topped "Vegas" among young viewers on Tuesday to help NBC take the night in the key demographic, but it was still a CBS rout overall, thanks to the "NCIS" double-bill.
 
Meanwhile, ABC's new Tuesday comedy block hemorrhaged overall viewers, but held up reasonably well in the key demo, while FOX's "The X Factor" delivered weak numbers in an out-of-slot, rescheduled airing.
 
And "Emily Owens, MD" drooped in its second week, though with CW numbers, you never know when that's just a random statistical fluctuation.
 
On the the ratings...
 
Among adults 18-49, NBC averaged a 2.7 rating for Tuesday night, edging out CBS' 2.5 rating in the key demographic. FOX's 2.0 rating and the 1.8 rating for ABC followed in the key demo. The CW did a 0.4 key demo rating for Tuesday.
 
Overall, though, CBS dominated by averaging 14.77 million viewers and a 9.4 rating/15 share, far ahead of ABC's 5.0/8 and 7.46 million viewers. NBC was third with a 4.3/7 and 7.05 million viewers, with FOX's 2.7/4 and 4.42 million viewers and distant fourth. The CW averaged 1.21 million viewers and a 0.9/1.
 
8 p.m. - "NCIS" ruled the 8 p.m. hour overall for CBS with 17.345 million viewers and finished second with a 3.2 rating among adults 18-49, down from the show's last original two weeks ago. ABC's "Dancing with the Stars" was second overall with 12.71 million viewers and third with a 2.2 key demo rating, inching up from last week. NBC's "The Voice" was also down with 10.905 million viewers and an hour-winning 4.1 key demo rating. On FOX, "Raising Hope" (4.13 million and a 1.7 key demo) and "Ben and Kate" (3.05 million and a 1.4 key demo) were fourth. The CW's "Hart of Dixie" averaged 1.31 million viewers and a 0.5 key demo rating, basically flat from last week.
 
9 p.m. - "NCIS: Los Angeles" won the 9 p.m. hour overall with 16.25 million viewers and with a 2.7 rating among adults 18-49, rising episode-to-episode in viewers, but dipping in the key demo. "NCIS: Los Angeles" outdrew the combined averages for the comedy blocks on ABC, NBC and FOX for the hour. NBC was second overall but third in the key demo with "Go On" (6.41 million and a 2.5 key demo) and "The New Normal" (4.49 million and a 1.8 key demo). FOX was third overall and second in the key demo with "New Girl" (5.23 million viewers and a 2.7 key demo) and the first half-hour of "X Factor" (5.27 million and a 2.3 key demo). And ABC's comedy block was fourth with "Happy Endings" (5.93 million viewers and a 1.9 key demo) and "Don't Trust the B---- in Apartment 23" (4.28 million and a 1.7 key demo). On The CW, "Emily Owens, MD" averaged 1.11 million viewers and a 0.3 key demo rating. 
 
10 p.m. - "Vegas" ruled the 10 p.m. hour overall with 10.72 million viewers, but dropped a solid half-point in the key demo with a 1.5 rating, good only for second for CBS. NBC's "Parenthood" averaged 4.79 million viewers and won the hour with a 1.9 rating among adults 18-49. ABC's "Private Practice" plummeted with 4.56 million viewers and a 1.4 key demo rating, mostly as a result of a weaker lead-in.
 
All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.