Friday the 13th etc.) of the year. Any month that starts on a Sunday contains a Friday the 13th, and there is at least one Friday the 13th in every calendar year. There can be as many as three Friday the 13ths in a single calendar year; either in February, March and November in a common year starting on Thursday (such as 2009, 2015 or 2026) (D), or January, April and July in a leap year starting on Sunday (such as 2012) (AG). The longest period that occurs without a Friday the 13th is 14 months, either from July to September the following
Leap year starting on Saturday one Friday the 13th; The only Friday the 13th in this leap year occurs in October. Common years starting on Sunday share this characteristic, but also have another in January. From August of the year that precedes this year until October in this type of year is also the longest period (14 months) that occurs without a Friday the 13th. Common years starting on Tuesday share this characteristic, from July of the year that precedes it to September in that type of year. There are two other ways this 14 month interval can be formed, one involving a common year