Monday Holidays and President's Day

Quite some time ago, I do not remember when, Federal holidays were homogenized into Monday Holidays, instead of the actual day... Not always, but mostly:  For example, instead of a holiday on February 12 for Lincoln, and another on February 22 for Washington, we have President's day on the third Monday of February. 

Martin Luther King Day is the 3rd Monday of January.  Memorial Day is the last Monday of May. Many places do not celebrate Columbus Day, but those that do tend to celebrate the second Monday in October.

Of course, Thanksgiving is still the 4th Thursday in November.  Labor Day is the first Monday in September.

Days that retain their date include the 4th of July, Christmas and New Years. Even so, many entities wrap these holidays with extra days off to give long weekends.