New Line/Warner BrosIt continues to break records drawing $8.8M yesterday which is the highest Monday that the month of September has ever seen. Previous Monday high in September was The Sixth Sense‘s Labor Day Monday of $6.37M back in 1999.

In addition, in a matter of hours, It will be the highest grossing Stephen King movie of all-time at the domestic box office, surpassing the $136.8M take of 1999’s The Green Mile. To date there’s been 33 King titles adapted to the big screen. Through four days, It counts $132.2M.

As we said in our weekend coverage, what box office record didn’t It break? The Andy Muschietti-directed movie owns the best opening day ever for a horror title ($51M), the highest pre-show for a horror film, one in September and for an R-rated movie ($13.5M), the highest three-day opening record weekend for the genre and the second-highest opening for an R-rated pic (behind Deadpool‘s $132.4M), the best September opening for any genre which means the best September opening to date for the studio.

Estimates for It‘s second weekend are in the mid $50M range –another record weekend for September– as it squares off with another horror-thriller, Paramount’s mother! from Darren Aronofsky and Lionsgate’s American Assassin.