On Labor Day, cinemas are usually stuck in the doldrums. This year, it’s the worst Labor Day weekend for the domestic box office in two decades.

But for VOD rentals on pay-TV providers, America’s unofficial end to summer zooms off the charts.

Over the last three years, VOD rental transactions have been approximately 100% higher on Labor Day compared with the average rate of other Mondays, according to marketing data analytics provider one2one Media. Video-on-demand customers on Labor Day are primarily women 25-54, according to one2one. The company obtains data from sources including comScore/Rentrak and more than 40 pay-TV operators.

Comcast‘s own data backs up those findings: On Labor Day 2016, the cable giant’s VOD revenue was up 97% compared to other Mondays in August 2016.

What’s behind VOD’s Labor Day festivities? Here are a few reasons to explain the bump for the U.S. holiday that falls on the first Monday in September:

1. Studios don’t usually open big movies over Labor Day, while summer blockbusters are on VOD. Home-video activity in early September is likely a beneficiary of Hollywood’s release-window cycle. Studios don’t schedule tentpole releases on Labor Day weekend, because it bumps into the start of the new school year. Meanwhile, the biggest theatrical titles of the summer have now arrived on VOD: Currently, Warner Bros.’s “Wonder Woman,” the biggest movie of the summer of 2017, is now available on video-on-demand, along with Disney-Marvel’s “Guardians of the Galaxy Vol. 2,” “Alien: Covenant,” and “King Arthur: Legend of the Sword.”

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2. School’s back in session. Families have often concluded their summer vacations by Labor Day, and in most areas the school year has either already started or is about to commence. That means lots of people are parked at home, with a VOD movie just a few button pushes away.

3. It’s a big drinking holiday. It’s no coincidence that New Year’s Eve is the other major day on the calendar when VOD rentals skyrocket — similarly seeing about a twofold increase in activity, according to one2one. After a few beers, it seems, people are more willing to shell out a few bucks for a VOD title.

4. Not much is happening on TV. The fall television premieres haven’t started yet, and there aren’t any major sporting events on TV aside from the U.S. Open tennis tournament (which this year features women’s and men’s singles matches in the Round of 16).

So if you’re like many Americans, today you may be filling up the cooler, lighting the grill — and firing up the VOD.

Pictured above: Verizon’s Fios current on-demand new releases movie menu.