NFL ratings dropped almost 10 percent in 2017 from the previous year according to Nielsen data released on Thursday, a further decline in the decreased TV viewership from 2016 that saw an 8 percent drop.

The average number of games watched by viewers throughout the season dropped from 18.8 in 2015 to 16.5 in 2017.

Several factors appear to have influenced the decreased interest from fans in watching games, with a Los Angeles Times report pointing to evidence that suggests controversy over players kneeling for the national anthem played a role early in the season.

The L.A. Times spoke with Fox Sports executive Mike Mulvihill, who shared some numbers from the network. Fox’s Sunday package saw an 8 percent decline in Weeks 2 through 10 when the anthem controversy was at its peak, spurred on by commentary from President Donald Trump.

During Weeks 11 through 17, the drop in viewership shrunk to 2 percent for the network.

Viewers upset with players kneeling and others not satisfied with the NFL’s handling of the Colin Kaepernick situation that saw the quarterback miss the entire season appear to have tuned out.

A more compelling slate of national games and better quality of play as the season wore on and the playoff picture cleared up likely played a factor in the the late-season shift as well.

Mulvihill also pointed to a changing demographic that consumes its entertainment in non-traditional media, most notably YouTube, in this case.

“The audience for NFL highlights on YouTube have become pretty substantial,” Mulvihill said. “Those highlights can be eight, nine or 10 minutes long, and I do worry they can be serving as a disincentive from watching the live game.”

Mulvihill is clearly concerned about a younger audience less interested in sitting down for three-plus hours to watch a single game play out. He also theorized that more people are watching the news on Sundays with the volatile political climate being a big television draw, piggybacking on the wide-held belief that the election last year played a role in the declining 2016 numbers.

Despite the declining numbers, NFL viewership is still king on broadcast TV, by a wide margin. AdAge analysis shows that NFL broadcasts accounted for 37 of the 50 most watched broadcasts in 2017. NBC’s “Sunday Night Football” remained No. 1 prime-time show on TV.

But that doesn’t mean network heads aren’t concerned. With CBS, Fox, NBC and ESPN each paying at least $1 billion for broadcasts rights, the stakes are high. And, according to an anonymous network executive who spoke with the L.A. Times, each of those networks “made a lot less money than they expected” in 2017.

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