Jay Leno's Tonight Show slipped back Conan's adults 18-49 ratings on a calendar week basis (2010 vs. 2009). In the last five weeks, Leno has tied Conan three times, and now trailed twice. Leno's Tonight Show for the week of August 2-6 were 0.1 behind Conan's Tonight Show ratings for the comparable calendar week last year(August 3-7, 2009).
As has been the case in all but a couple of weeks since returning to late night in March, Leno came out ahead of Letterman, though Letterman was flat vs. last summer while Tonight Show was down 0.1. with adults 18-49.
The chart shows the late night adults 18-49 weekly average ratings for 2009 and 2010.
Note: The week ending 7/2/2010, the Tonight Show was in repeats, and was delayed by Wimbledon coverage. The week of 7/9/2010 the Late Show was in repeats, and both shows Monday airings were excluded because of the holiday. For the weeks ending 7/16-8/6, Late Show was a repeat only on Friday.
No more chart of the sequential weeks comparison between Conan and Leno. That chart was always a bit apples/oranges because of the different seasons. While before the calendar runs of the shows overlapped we had to make do, now that we have some of the same time period to compare, the sequential chart has been retired.