Last year, the NFL lost about a million regular-season viewers versus the 2013 and 2014 seasons. It represented about a 6% fall-off ― enough to be easily noticed and maybe even cause a little concern, but it could be written off as a one-year blip. Last year's seepage has turned into a major break in the dam. The league is now down about three million viewers per game from 2013 and 2014. When the specific teams appearing, the scope of the telecast and the week of the season are taken into account, the decline is even more dramatic: more than four million viewers, or in excess of 20%.

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