Common year starting on Friday has only one Friday the 13th; The only Friday the 13th in this common year occurs in August. Leap years starting on Thursday share this characteristic, but also have another one in February. This is the only year type where the "n"th "Doomsday" (this year Sunday) is not in ISO week "n"; it is in ISO week "n"-1. In the (currently used) Gregorian calendar, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-three common years per cycle or exactly 10.75% start on a Friday. The 28-year sub-cycle does only span across century
Friday the 13th death on Good Friday. While there is evidence of both Friday and the number 13 being considered unlucky, there is no record of the two items being referred to as especially unlucky in conjunction before the 19th century. An early documented reference in English occurs in Henry Sutherland Edwards' 1869 biography of Gioachino Rossini, who died on a Friday 13th: He [Rossini] was surrounded to the last by admiring friends; and if it be true that, like so many Italians, he regarded Fridays as an unlucky day and thirteen as an unlucky number, it is remarkable that on Friday 13th