13 Facts about Friday the 13th

1. In the U.S., between $800 million and $900 million of revenue is lost to businesses every year on Friday the 13ths because people are afraid to travel, shop, or even get out of bed and go to work.

2. Any month that starts with Sunday will have a Friday the 13th.

3. Every year has at least one Friday the 13th, but no more than three.

4. Fridays are the day most likely to be the 13th.

5. Although the number 13 and Fridays were considered unlucky independently for centuries, the origins of being particularly wary of Friday 13th are unknown. This specific fear didn’t pop up until the 19th century.

6. On Friday, 13 October 1307, hundreds of the Knights Templar were arrested in France, long before Friday and 13 were considered a bad combination. Dan Brown’s book The Da Vinci Code popularized this connection to the superstition.

7. Fear of Friday the 13th is called paraskevidekatriaphobia

8. In 1882, Civil War vet Captain William Fowler founded The Thirteen Club to dispel the myth that 13 is a bad number. Their first meeting was held Friday, January 13, at 7:13 p.m. The group of 13 walked under a ladder, then spilled some salt without throwing it over their shoulder. (Taylor Swift would have loved them.)

9. Part of the fear of thirteen comes from a belief that if thirteen people eat together, one of the diners will die. This superstition is tied to Last Supper and an old Norse myth.

10. In Spanish speaking countries and Greece, Tuesday the 13th is considered unlucky.

11. Although less people go out on Friday the 13th in English speaking countries, it’s generally more safe than other Fridays because everyone is driving more carefully.

12. The earliest known reference to Friday the 13th as unlucky comes from a 1869 biography of Gioachino Rossini, who died on a Friday the 13th.

13. Friday the 13th will occur three times in 2015, in February, March, and November. The next time it will happen three times in one year will be 2026.