Fast National ratings for Monday, September 27, 2010.
 
It wasn't a great week for retention, as every single one of the five new Monday network shows slipped in Week Two, with "The Event" taking a particularly big dive and FOX's "Lone Star" continuing to sink deeper into the Cancellation Danger Zone.
 
Meanwhile, with the new shows all slipping, "Dancing with the Stars" showed improvement in its second week, as ABC dominated Monday night in all key measures.
 
Among adults 18-49, ABC averaged a 4.3 rating, topping the 3.7 rating for CBS in the key demographic. FOX's 2.5 rating and the 2.3 rating for NBC followed. The CW's 1.0 rating was fifth. 
 
Overall, ABC averaged an estimated 18.5 million viewers to go with an 11.8 rating/18 share. CBS was a distant second with an average of 11.146 million viewers and a 6.9/11. There was another big drop to FOX in third with 6.92 million viewers and a 4.2/6, which edged the 4.1/6 and 6.89 million viewers. The CW was fifth with a 1.3/2 and 1.876 million viewers.
 
In the 8 p.m. hour, ABC's "Dancing with the Stars" averaged 20.225 million viewers and a 4.3 demo rating, both tops for the hour. FOX was second with the 10.05 million viewers and a 3.7 demo rating. CBS' "How I Met Your Mother" and "Rules of Engagement" averaged 8.557 million viewers for third. On NBC, "Chuck" had 5.32 million viewers and a 1.9 demo rating, both down from last week. The CW's "90210" averaged 1.97 million viewers for fifth.
 
"Dancing with the Stars" improved to 22.92 million viewers and a 5.3 demo rating in the 9 p.m. hour. CBS was second with "Two and a Half Men" (13.87 million) and "Mike & Molly" (11.21 million, down by over a million). On NBC, "The Event" averaged 8.98 million viewers and a 2,9 demo rating, down steeply from 11.2 million and a 3.7 demo in last week's Fast Nationals. FOX's "Lone Star" averaged 3.78 million viewers and a 1.3 demo rating, though those numbers are skewed by FOX running "House" into the 9 p.m. hour. In its second half-hour, "Lone star" was down to 3.04 million viewers and a 0.9 demo. In that second half-hour, "Lone Star" actually finished behind The CW's "Gossip Girl" in the demo, as "Gossip Girl" averaged 1.78 million viewers overall.
 
ABC's "Castle" averaged 12.36 million viewers to win the 10 p.m. hour overall. CBS' "Hawaii Five-0" dropped to 12.34 million viewers, but still won the hour with a 3.5 demo rating. NBC's "Chase" was third with 6.36 million viewers and a 2.1 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.