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
Black Friday (shopping) and small retailers that used Black Friday in their marketing. However, with a total of 35 participating stores, 2015 can be considered the year in which Black Friday started in the Netherlands due to more widespread support of large retailers. The popularity of Black Friday has grown rapidly in the Netherlands. The number of participating stores has increased to over 125 during the Black Friday period of 2017. In 2016 Black Friday was introduced in Poland, Greece and Ukraine. Black Friday in Belgium is seriously marketed by retailers since 2016. Especially online shops have broke sales records during the last