Presidents' Day [officially Washington's Birthday] celebrated in the United States, is a federal holiday observed on the third Monday of February in honor of George Washington (born on February 22), the first President of the United States. The holiday is popularly recognized as also honoring Abraham Lincoln (born on February 12) and sometimes all the U.S. presidents.
The federal holiday commemorating Washington was established in 1879 for government offices in Washington only and later (1885) expanded to the whole country. The Uniform Monday Holiday Act from 1968 changed the date to the third Monday in February (effective as of 1971). As of 1971 and depending on a given (Gregorian calendar) year, the date of Presidents' Day falls between February 15 and 21. Hence it never occurs on February 22, i.e., actual Washington's birthday. Similarly, it also misses Lincoln's Birthday on February 12.
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The Presidents (Washington to Monroe)
The Presidents (Taylor to Lincoln)