An actor is seen inside the Legend of Sleepy Hollow room at Nightmare: New York, a haunted house for adults, in New York on Oct. 22, 2014. (Mike Segar/Reuters)

For some reason, humans like to scare ourselves. We pay money to go watch poorly made horror movies in which people are ripped to shreds and then we tell other people to go see those movies, too. We convince ourselves — sometimes sincerely — that certain things are particularly scary or unlucky. Black cats. Clowns. Skeletons. Our society has internalized these weird ideas to the extent that many skyscrapers still don’t have buttons for the 13th floor of a building, as though calling the 13th floor the 14th floor is a critical measure toward keeping everybody safe.

And then there’s Friday the 13th. Or, if you’re reading this on Friday: Today. Friday the 13th has itself starred in some of those terrible horror movies — as you know because it’s a very popular movie franchise.

Why are we afraid of the day? (“Afraid.”) National Geographic talked to an expert, psychologist Stuart Vyse, who speculated that the origins lay in the Christian religion. The number 13 is unlucky/scary because of the 13th guest at the Last Supper — Judas Iscariot, who betrayed Jesus to the Roman authorities. Fridays are unlucky, the article explained, because it was apparently a Friday on which Adam and Eve ate the forbidden apple in the Garden of Eden. (This raises the amusing idea of Adam and Eve being aware of weekdays. “What do you want to do on Saturday?” “Let’s go upstate and check out some antique stores.”) Also, I guess, it was perhaps a Friday the 13th when Cain killed Abel. So say the experts, who know better than me.

On rare occasions (14 times in the past century), Friday the 13th — the scariest day of a month — occurs in October, the scariest month of the year. This is a triple-whammy of terrifying, as you are no doubt aware as you cower your way through the day today.

The overlap of Friday the 13th and the Halloween season and movies about how people are routinely murdered on those days made us wonder: Just how lucky have all of us been? I can remember several Friday the 13ths on which I was not murdered by a serial killer and none on which I was. Just how many brushes with death have I avoided over the course of my life?

Computers can answer that question! Here’s how many.

Let us then treat Friday the 13th of October not as a day of scariness but one of celebration. We’ve survived so many of these! Despite constant serial-killer attacks and supernatural monsters slashing at us with razor blades, here we are, wasting time on the Internet like it’s just any other day.

The interactive above includes today, by the way. If you are killed by a serial killer before midnight, please let us know so we can adjust the numbers downward.

This article has been corrected to clarify Vyse’s comments to National Geographic.