Anderson is the mastermind of the National Day Calendar, an online compendium of pseudo-holidays that has become a resource for TV and radio stations looking to add a little levity to their broadcasts. The 52-year-old co-owner of a VHS digitizing company in North Dakota started the calendar in 2013 and soon realized the site could also be a way for people to declare their own special days. Marketing experts give Anderson credit for seizing on the desire by companies and groups for another way to promote themselves, though they question the effectiveness some of the resulting campaigns. In 1870, Congress established the first four federal holidays with New Year's Day, Independence Day, Thanksgiving and Christmas. [...] only six more annual federal holidays have been added, with the most recent being Martin Luther King Jr.