According in the exploitation industry, the weakest box office days were "T-to-T".
In other words: Tuesday, Wednesday, Thursday.
If you're exhibiting your movie independently, consider bombastic spectacles, free giveaways, or any kind of gimmick to draw an extra crowd in during these days.
This could apply to online efforts,
like content marketing.
Producer Kroger Babb, during the Great Depression, drew people into theaters between Tuesday and Thursday by hosting a "Grocery Night."
A unique number was printed on each movie ticket, and whatever lucky moviegoer won the raffle that night would win a ten-dollar bag of groceries.
That was a lot of food back then.
Consider: a movie ticket was twenty five cents during the 1930s.
Kroger struck a deal with a local grocery store to pay for the advertising in exchange for Kroger's aggressive & spectacular promotion of the grocery store to his movie audiences.
Whoever agreed to this deal suddenly were promoted as having the finest, biggest, best, juiciest, most delicious and nutritious food... at least, according to Kroger Babb.