In a sign of their declining popularity, late-night comedians Jimmy Kimmel, Stephen Colbert, and Jimmy Fallon have seen their ratings plummet for more than four months straight, as viewers in the coveted 18-49 year old demographic are tuning out consistently compared to last year, according to data reviewed by Breitbart News. For last week, the three major late-night shows experienced a 19 percent drop from last year in their average weekly viewership in the 18-49 demographic. These declines tend to be between 10 percent and 20 percent every week as far back as mid July, though some weeks saw even...