The NFL's once-golden network TV numbers continue to drop.

NFL games averaged 15.1 million viewers through Week 7, according to Nielsen data obtained by Sporting News. That's down 5.1 percent from 15.87 million viewers during the same period last season and off 18.7 percent from 18.35 million viewers during the same period in 2015.

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Viewership numbers are lagging for a variety of reasons, not least the ongoing protests during the national anthem that former 49ers quarterback Colin Kaepernick began in 2016. Fans are still angry about Kaepernick’s continued unemployment as well as what's seen as the growing politicization of the NFL.

In addition, President Donald Trump continues to attack the league for not forcing all players to stand during the anthem. Commissioner Roger Goodell and player reps met last week to seek a way forward, but there wasn’t much progress, and players continue to protest.

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More than 20 NFL players sat, took a knee, raised a fist or stayed in the tunnel during Week 7 games, according to The Associated Press.

The NFL’s network TV partners, for their part, refuse to show, much less discuss, player protests on the air during game telecasts after airing them for a brief time earlier in the season.

Across the media landscape, viewers are watching less sports on TV. The NFL is also missing an All-Pro team of injured stars including Aaron Rodgers, Odell Beckham Jr. and J.J. Watt. Former draws such as Peyton Manning and Tony Romo are now retired.

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The good news: National draws such as the Cowboys, the Steelers and the Super Bowl-champion Patriots are rebounding from early-season struggles.

The league is also benefiting from new stars like Carson Wentz of the Eagles.