David Letterman's final "Late Show" hits 20-year ratings high

David Letterman's farewell from the "Late Show" was the late-night program's most watched episode in more than two decades.

The star-filled telecast drew 13.76 million viewers, according to Nielsen, giving it the show's largest audience since February 1994 (when he followed CBS' primetime coverage of the Winter Olympics).

Wednesday's sendoff, which featured a final Top 10 list and cameos from celebrities and presidents, also notched a 3.1 rating with adults 18-49 and 4.1 with adults 25-54, the highest ratings in those demographics since December 2005, when Oprah Winfrey appeared on the show.

The ratings bump also meant good news for James Corden and the "Late Late Show," which brought in 4 million viewers for its post-Letterman episode -- marking an all-time audience record for that late-night show, with any host.