I've never been superstitious, but many people believe strongly of the unluckiness of Friday the 13th.
Livescience.com reports that Igor Radun of the Human Factors and Safety Behavior Group at the University of Helsinki's Institute of Behavioral Sciences in Finland, said "No data exists, and will never exist, to confirm that the number 13 is an unlucky number." "There is no reason to believe that any number would be lucky or unlucky."
But the article does show evidence that many factors, including car accidents, are more likely to occur on Friday the 13th, than on any other Friday. I guess you'll have to decide for yourself! You can read the full article from livesciece.com here.