Just a sample site of a possible usage of DateTimeExtensions nuget package.
January 02 New Year Observed
March 07 AshWednesday
April 20 Good Friday
April 23 Easter Monday
May 23 Labor Day
August 01 Emancipation Day
August 06 Independence Day
October 15 National Heroes Day
December 25 Christmas
December 26 Boxing Day
DateTimeExtensions DateTimeExtensions