Things are not going well lately for Conan O’Brien. The Tonight Show’s fall to the bottom of its timeslot ratings was punctuated Wednesday when David Letterman pulled in 4.4 million viewers while Conan drew just 2.5 million, the Baltimore Sun reports. That’s the worst number for the Tonight Show since measuring started. To be fair, the Late Show featured Paul McCartney's first performance at the Ed Sullivan Theater since 1964, but the disparity wasn't atypical, reports the New York Times.
Last week Conan came in a distant third, with Michael Jackson coverage powering Nightline to 3.8 million viewers, ahead of Letterman’s 3.7 million and Conan’s 2.8 million. Conan is still winning with young audiences—his 18-to-34 numbers are up 26% over Leno’s—but NBC is nervous. “Dave is definitely on his game,” said one NBC executive. “Conan has to respond.”