The NFL is getting a very encouraging sign for TV ratings this season

The National Football League's TV ratings look to be back on the upswing.

That's according to UBS, which uses the NFL's preseason viewership as an early indicator for how many eyeballs the league's more coveted regular season broadcasts will attract.

NFL higher-ups could use some good news after ratings of regular season games in 2016 fell 8% on a year-over-year basis, according to UBS analyst Doug Mitchelson. Luckily, preseason matchups drew 12% more viewers this year, signaling a rebound to come for the most lucrative professional sports league in the US.

As highlighted in the chart above, the preseason is finishing on a high note, with ratings for the third warm-up game increasing 7% year-over-year. The third game is usually the last one in which starters play, making it the last truly meaningful data point.

What's more, last Sunday's primetime game saw a 16% viewership bump from 2016, despite going head-to-head with ratings juggernaut Game of Thrones.

But why all the fuss over preseason ratings? Do they really matter?

Absolutely, says UBS, which notes that there's been a notable correlation between preseason and regular season viewership, dating back years. This is particularly true when comparing ratings on major networks, including CBS, ESPN, Fox and NBC. (The rest of games can be found on NFL Network or local affiliates.)

In the chart below, you'll note this year's preseason uptick, which foreshadows a recovery in regular season ratings.

Lastly, one important thing to note about NFL ratings is that, while their trajectory is always a source of worry, the sport still dominates the airwaves. NBC's Sunday Night Football is always among the most-watched TV events during a given week, and the 2016 Super Bowl was the most-watched broadcast last year - handily beating out the presidential debates.