Robert Griffin III

Redskin star Robert Griffin III helped keep the NFL on top of ratings race. (Getty Images / January 4, 2013)

The National Football League is still the most dominant programmer in television, but even it is not immune to shrinking audiences in an overcrowded media landscape.

Not only that, but the median age of the typical NFL viewer went up from 46 to 47. That is significant because advertisers place a greater preimum on younger viewers, and 47 is just three years away from the dreaded 50.

According to an examination of Nieslen numbers by the ubiquitous media analyst Brad Adgate of the advertising firm Horizon Media, only the NFL Network saw a spike in viewers with its Thursday night football games. CBS, NBC, Fox and ESPN all had smaller audiences for the 2012 regular season.

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NBC was still the leader among the networks that carry football, with its Sunday night game averaging 21.4 million viewers. While that makes it the most popular show on television, it was also off by almost 1% from a year ago. CBS's Sunday afternoon games averaged 17.7 million viewers, which was off by 4% compared with last season. ESPN's audience fell 3.3% to 12.8 million viewers.

The NFL Network's numbers for its Thursday games was up almost 3%. Not only did the network carry more games this season, it also finally had landed distribution on Time Warner Cable and Cablevision Systems, two big pay-TV operators.

The declining numbers come when all the networks are paying extraordinary amounts of money for football. New deals kick in next season with News Corp.'s Fox paying an average of $1.1 billion per season, CBS shelling out just more than $1 billion and NBC's cost is just under $1 billion. ESPN's average fee for "Monday Night Football" is $1.9 billion.

Given how tough it is for advertisers to reach a mass audience, even slightly smaller ratings won't necessarily hurt commercial rates for football.

While ratings for most television shows have declined as more channels and viewing options emerge, the NFL may also be guilty of self-inflicted wounds. More games on Thursday and the growing popularity of the league's RedZone channel, which shows live action from all the games every Sunday could be taking away viewers from the big rights holders.

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NFL RedZone keeps its eye on the games

Rising sports programming costs could have consumers crying foul

Follow Joe Flint on Twitter @JBFlint.

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