Ads could be just as much to blame as player protests and the cratering of cable TV subscriptions for the sinking viewership for NFL games, according to a new study from Streaming Observer, a website that covers streaming media.

Thursday night’s 13.4 household rating for NBC’s broadcast of the Philadelphia Eagles’ 18-12 victory over the Atlanta Falcons was down about eight percent from the 14.6 rating for last year’s opener between the Kansas City Chiefs and New England Patriots. Back in 2015, the Patriots and Pittsburgh Steelers brought in a record-setting 17.7 rating.

While a 45-minute weather delay (resulting in a game that didn’t end until after midnight) could certainly be behind some of that dip, Streaming Observer’s Chris Brantner suggests that the continuing overload of advertising is also driving lower viewer numbers.

According to his report, the NFL’s moves to reduce the effect of ads on the viewing experience have had little, if any, benefit. While the number of commercial breaks per quarter has been reduced from five to four, the study says the total number of ads broadcast has not seen a similar decline.

Because of that, Streaming Observer estimates that the “average NFL fan” will watch 24 hours of commercials over the course of a season. With an estimated 83.1 minutes of ads for each game, that racks up to a full day’s worth of commercials—and that doesn’t even take the playoffs into consideration.

Despite its decline, whether ad-related or not, the NFL remains the 10-ton gorilla of broadcast TV. To put things in context, primetime ratings for Thursday’s game were more than triple those of the combined viewership for the night’s programming on CBS, ABC, Fox and The CW. The NFL boost also extended into NBC’s late-night schedule, with ratings for the Tonight Show and Late Night easily topping their competition.