CBS' "Late Show with Stephen Colbert" completed the September-to-September TV seasonal period ahead of other competitors -- in a big way among all viewers, and with a narrower lead among key 18-49 viewers.
Among the shows starting at 11:35 p.m., "Late Show" pulled in a Nielsen-measured 3.61 million viewers (through September 20) -- well above NBC’s "Tonight Show with Jimmy Fallon," which scored 2.29 million, and ABC’s "Jimmy Kimmel Live," which came in at 1.97 million.
Versus the year-ago time period, "Late Show" was down 4% (from 3.75 million), while "Tonight" lost 11% (2.57 million); and "Kimmel" gave up 9% (2.17 million).
Among 18-49 viewers, it was a much closer competition: "Late Show" came in at a Nielsen 0.49 rating/4 share, with "Tonight" at a 0.48/3 and "Kimmel" at an 0.38/3.
NBC did take top honors later in the evening, for "Late Night with Seth Meyers," with 1.38 million average viewers; CBS' "Late Late Show with James Corden" at 1.29 million; and ABC’s "Nightline" at 1.23 million.
Other late night time period programming: NBC’s “A Little Late With Lilly Singh” (1:35 a.m.) 610,000 viewers; TBS’ Adult Swim block (11:30 p.m.), 660,000; Adult Swim (12:30 a.m.), 550,000; Comedy Central’s “Daily Show with Trevor Noah” (11 p.m.), 590,000; TBS’s “Conan” (11 p.m.), 320,000; and Comedy Central’s “Lights Out with David Spade”(11:30 p.m.), 250,000.
Just look at those numbers, folks. If I were targeting the "key" viewer group" ---the all important 18-49s--- and decided to buy "roadblock positions on all three networks at the same time, for their premiere late night entries I might "reach" 1.4% of my target---but that's no guarantee that they would watch my commercial.