Fast National ratings for Wednesday, Jan. 21, 2009.

FOX's "American Idol" improved on its lower-than-expected Tuesday performance, while the season premiere of ABC's "Lost" drew in younger viewers on Wednesday.

Among adults 18-49, FOX averaged a 7.4 rating, far ahead of ABC's 4.5 rating. CBS' 2.9 rating and the 1.9 rating for NBC followed. The CW had a 0.5 rating for fifth.

Overall, FOX averaged an estimated 19.3 million viewers, plus an 11.0 rating/17 share. CBS took second with a 7.0/11, followed closely by the 6.2/10 for ABC. NBC's 4.3/7 and The CW's 0.8/1 followed.

At 8 p.m. FOX got a 14.3/22 from "American Idol," drawing 25.43 million viewers. ABC's "Lost: Destiny Calls" special with second, beating the 4.7/7 for CBS' "New Adventures of Old Christine" and "Gary Unmarried." NBC had a 3.2/5 for "Knight Rider." The CW's "13 - Fear Is Real" had a 0.9/1.

CBS moved into first place at 9 p.m. with an 8.7/13 for "Criminal Minds." FOX was second with the premiere of "Lie to Me," which fell to a 7.7/12 from its lead-in. ABC was third with a 6.8/10 for the first hour of the "Lost" premiere. NBC's "Law & Order: Special Victims Unit" was fourth, beating The CW's "90210."

CBS won the 10 p.m. hour with a 7.7/12 for "CSI: NY." ABC's "Lost" won the hour in the 18-49 demo and had a 6.4/10 for the hour, topping "Law & Order" on NBC. Overall the "Lost" premiere underperformed last year's season averages. 

All ratings information comes from preliminary Fast National data, which includes live and same-day DVR viewing. All numbers are subject to change.