Friday the 13th occurs when the thirteenth day of a month falls on a Friday, which superstition holds to be a day of bad luck. In the Gregorian calendar, this day occurs at least once, but at most three times a year. Any month’s 13th day will fall on a Friday if the month starts on a Sunday.

Consequently, several theories have been proposed about the origin of the Friday the 13th superstition.

One theory states that it is a modern amalgamation of two older superstitions: that thirteen is an unlucky number and that Friday is an unlucky day.

In numerology, the number twelve is considered the number of completeness, as reflected in the twelve months of the year, twelve hours of the clock, twelve tribes of Israel, twelve Apostles of Jesus, twelve gods of Olympus, etc., whereas the number thirteen was considered irregular, transgressing this completeness. There is also a superstition, thought by some to derive from the Last Supper or a Norse myth, that having thirteen people seated at a table will result in the death of one of the diners.

Black Friday has been associated with stock market crashes and other disasters since the 1800s. It has also been suggested that Friday has been considered an unlucky day because, according to Christian scripture and tradition, Jesus was crucified on a Friday.

The fear of Friday the 13th is called friggatriskaidekaphobia. People who have this phobia are probably anxious by now.

According to the Stress Management Center and Phobia Institute in Asheville, North Carolina, an estimated 17 to 21 million people in the United States are affected by a fear of this day. Some people are so paralyzed by fear that they avoid their normal routines in doing business, taking flights or even getting out of bed. “It’s been estimated that [US]$800 or $900 million is lost in business on this day”. Despite this, representatives for both Delta and Continental Airlines say that their airlines do not suffer from any noticeable drop in travel on those Fridays.

Ironically, there are fewer accidents and other unlucky incidents being reported on Friday the 13th compared to other Fridays of the month. The Dutch Centre for Insurance Statistics on June 12, 2008, stated that “fewer accidents and reports of fire and theft occur when the 13th of the month falls on a Friday than on other Fridays, because people are preventatively more careful or just stay home.”

This year, Friday the 13th will only occur once…today. But next year, there will be 3 Friday the 13ths, that’s on January, April and July. Plus add to that the Mayan prophecy that the world will end in 2012.

Did I make you more anxious? Don’t be. These are all superstitions and I truly believe that if it’s your time, it’s your time, Friday the 13th or not.