The superstitious day of Friday the 13th has come to be known as an unlucky day in most cultures and occurs at least once a year. However, those who prefer to avoid the stigmatized combination are in for more anxiety than usual because this year the day appears in three different months.

It is unknown exactly where and how the superstition began. Some believe it is because thirteen is said to be an unlucky number and Friday an unlucky day. Thirteen may be considered unlucky because in the past, it has represented completeness with twelve months in a year, twelve hours on a clock, and the twelve gods of Olympus. Many think the unluckiness of the number came from the story of the Last Supper where thirteen people were at the table. Furthermore, Jesus is said to have been crucified on a Friday, thus causing Friday to be an unlucky day.

Another theory of the origin of Friday the 13th is the story of the Knights Templar during the crusades. The Knights Templar were ordered to protect Christian pilgrims and soon acquired much wealth and power. Threatened by this, King Philip had them arrested on Friday, October 13th, 1307.

The fear of Friday the 13th is called paraskavedekatriaphobia and it is estimated that nearly 20 million people in the United States are affected by it. Many will change their normal actions by taking a different route to work, not flying, or not riding in cars. Some people won’t get out of bed at all. Because of this, an estimated 800 to 900 million dollars are lost in business on Friday the 13th.

But is Friday the 13th really unlucky? One study showed that traffic related accidents on this day increase dramatically. However, other studies show that there is a decrease in car accidents, thefts, and fires on the day because people are more cautious. Last Thursday, a Continental Airlines Flight crashed and caused a fire lasting in the morning hours of Friday the 13th.

There are plenty of superstitions that people follow. These vary from black cats, stepping on cracks, finding pennies, and rabbit feet, but no superstition is as popular as the unlucky day of Friday the 13th.