Just a sample site of a possible usage of DateTimeExtensions nuget package.
January 01 New Year
March 09 AshWednesday
April 22 Good Friday
April 25 Easter Monday
May 23 Labor Day
August 01 Emancipation Day
August 06 Independence Day
October 17 National Heroes Day
December 26 Christmas Observed
December 27 Boxing Day Observed
DateTimeExtensions DateTimeExtensions