Conan O’Brien’s premiere on The Tonight Show began with a bang on Monday, winning a household (HH) rating of 7.1, the highest for The Tonight Show on any Monday on  since 2005.

The show steadily lost viewers during the rest of its inaugural week but it managed to maintain an average above that of the second quarter 2009, established during Jay Leno’s run, as well as 62% lead on The Late Show with David Letterman. This is roughly double the margin The Tonight Show normally has. It will take some time for the ratings to indicate if The Tonight Show retains its lead. Another factor might be The Jay Leno Show, which premieres in September at 10:00 p.m. and which might cannibalize audience for NBC’s two nightly talk shows. The final outcome might be further well further off than 2009 though. Jay Leno’s started at The Tonight Show in 1992, and it wasn’t until 1995 that he took the lead against David Letterman.