According to ESPN, NFL ratings were down 9.7 percent during the 2017 regular season. If you don't care for percentages, and would rather that news be converted to raw numbers, that means that on average 14.9 million people watched a typical game this season as opposed to 16.5 million at this time last year. That represents a drop of roughly 1.6 million people per contest.
The development comes in addition to an eight percent slide in ratings from the 2015 season to the 2016 season. If you'll recall, that drop was chalked up (at least, in part) to the final stretch of the presidential election drawing interest away from the league.
While everybody has their own theories for why the NFL is losing eyeballs, this year's attempts to keep as much of the audience happy as possible was challenged by concerns over player safety, kneeling player protests, the blackballing of Colin Kaepernick, and the president himself tweeting/speaking about some variation of those topics.
In addition to those issues, there's also the ever present concern that Thursday Night Football is a watered-down nationally televised showcase of the sport. Furthermore, FOX CEO James Murdoch and CBS Sports chairman Sean McManus said the slide was brought about because there's too many damn games being televised.
As pointed out by ESPN, and what I personally find to be a very unscientific but good theory based upon my group of friends, the NFL RedZone could be a factor in drawing fans away from the full afternoon games being broadcast by FOX and CBS. Also pointed out by ESPN (and also a good theory) is that the fall could just come from general cord cutting, though it should be noted that NBA ratings are up 20 percent.
Still, it's not quite the death blow for the league that the Deadspin comment section has been crossing their fingers for for years. The Nielsen ratings still show that 20 of the 30 most viewed TV shows in 2017 were football games. On top of that, NBC and ESPN topped the most watched shows (for both the key male demographic, as well as total viewers) every single week with their airings of Sunday Night and Monday Night Football.
In fact, for the seventh straight year the NBC product (which would be Sunday Night Football) was the highest-rated show in primetime. With 18.2 million watchers per average episode they topped Thursday Night Football, which despite its obvious flaws was still second in primetime.