So there have only been 10? ;-)
Probably less. Titanic is the only one I can think of off the top of my head, plus a couple of “almosts” like 6th Sense which only suffered about 900K of drop with a 26 million start. It’s a very rare event in the modern era of wide release movies, their revenue picture is VERY front loaded. The average drop off is 30% per weekend if it’s not a “nerd” movie (comic book movies and similar), 45 to 50% per weekend for “nerd” movies.