Nielsen Top Twenty Shows Among 18-49 year olds for the week ending 01/18/09:
| Rank | Shows | R=Repeat S=Special P=Premiere | Net | 18-49 Rating | 18-49 Viewers (000) |
| 1 | AFC CHAMPIONSHIP ON CBS(S) | S | CBS | 14.7 | 19,350 |
| 2 | AMERICAN IDOL-WEDNESDAY | P | FOX | 11.8 | 15,573 |
| 3 | AMERICAN IDOL-TUESDAY | P | FOX | 11.7 | 15,483 |
| 4 | AFC CHMP POST GAME ON CBS(S) | S | CBS | 9.0 | 11,905 |
| 5 | CSI | CBS | 6.6 | 8,772 | |
| 6 | TWO AND A HALF MEN | CBS | 5.6 | 7,350 | |
| 7 | GREY'S ANATOMY-THU 9PM | ABC | 5.3 | 7,006 | |
| 8 | HOW I MET YOUR MOTHER | CBS | 4.8 | 6,302 | |
| 9 | DESPERATE HOUSEWIVES | ABC | 4.6 | 6,117 | |
| 10 | Mentalist, THE - SUN SPCL(S) | S | CBS | 4.6 | 6,081 |
| 11 | Big Bang Theory, THE | CBS | 4.4 | 5,822 | |
| 12 | OFFICE | NBC | 4.4 | 5,756 | |
| 13 | 24 | P | FOX | 4.1 | 5,376 |
| 14 | CSI: MIAMI | CBS | 4.1 | 5,366 | |
| 15 | Mentalist, THE | CBS | 3.8 | 5,041 | |
| 16 | NCIS | CBS | 3.7 | 4,924 | |
| 17 | CSI - 8PM SPECIAL(S) | SR | CBS | 3.6 | 4,802 |
| 18 | Law And Order:SVU | NBC | 3.6 | 4,700 | |
| 19 | ELEVENTH HOUR | CBS | 3.4 | 4,490 | |
| 20 | Biggest Loser 7 | NBC | 3.3 | 4,361 |
Nielsen TV Ratings Data: ©2008 The Nielsen Company. All Rights Reserved.
All numbers are Live + SD (live, plus same day DVR viewing)
