According to Dr. Donald Dossey of the Stress Management Center and Phobia Institute in Asheville, N.C., 17 to 21 million people In the U.S. (and another 4 to 5 million in the UK) suffer from paraskevidekatriaphobia, i.e, a fear of Friday the 13th. However, one in four Americans are superstitious and are likely to have even the smallest belief that some form of bad luck will show itself on these dreadful Fridays.