TBS scored with reruns of "The Big Bang Theory," a Chuck Lorre… (Robert Voets / CBS )
Prime-time network reruns, once a reliable source of ratings and advertising revenue, are losing their appeal as the entertainment landscape becomes more crowded with options.
A television viewership study released this week by RPA, a Santa Monica-based advertising agency, found that several long-term audience trends were reinforced during the most recent television season.
Key among them: Major networks struggle to hold onto younger viewers, two blockbuster shows witnessed an exodus of viewers, and reruns were less potent.
Ratings held up during the first half of the 2011-2012 TV season, but dropped sharply during the second half of the season. Double-digit declines for two important franchises -- "American Idol" on Fox and "Dancing with the Stars" on ABC -- were largely to blame.
"The ratings just collapsed for these two shows," RPA's veteran television analyst David Scardino said Wednesday. "Both the 'Dancing with the Stars' performance show and 'American Idol' on Wednesday were down 32% among viewers aged 18 to 49."
Another factor cited by RPA for the soft second half was the diminished ability of reruns to draw audiences. Reruns suffered sharper audience declines in the 2011-2012 season than during the previous season.
Rerun retention slipped 4% during the most recent season, mustering 48% of the audience for the original episode. During the 2010-2011 season, repeats generated 52% of the viewership for the original episode.
Among viewers ages 18 to 49, repeats retained 43% of the audience for the original episode, a decline of 3% from the previous season.
"Repeats just didn't hold the audience as well as they did in past seasons," Scardino said. "And it's logical: There are more places to see reruns."
For example, cable channel TBS got a ratings boost, in part, through the strength of the Warner Bros. produced sit-com, "The Big Bang Theory," which has its first run on CBS.
"TBS really caught a wave. It ran 'Big Bang Theory' more than 300 times across the season and it did extremely well," Scardino said.
RPA's report also found that USA Network leap-frogged ESPN to earn the ranking of sixth most popular TV network, behind CBS, Fox, ABC, NBC and Univision. Next came ESPN, Nickelodeon, TBS and History channel.
Meanwhile, Nick at Nite and TNT dropped out of the Top 10.
NBC's NFL package, "Sunday Night Football," was the most watched show on TV last season, drawing an average of nearly 20 million viewers a game.
The second most popular program was CBS' Navy procedural drama "NCIS," which averaged 16.6 million viewers. Fox's "American Idol" Wednesday edition, which averaged 16.3 million viewers an episode, was third, followed by ABC's "Dancing with the Stars," which averaged 15.8 million viewers an episode. NBC's "Sunday Night NFL Pre-Kick" show rounded out the Top Five with 15.5 million viewers a week.
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