Some person in authority -- I don't know who -- very likely the astronomer royal

"... has decided that,
although for such a beastly month as February,
twenty-eight days as a rule are plenty,

One year in every four
its days shall be reckoned as
nine and twenty."
-- The Pirate King, The Pirates of Penzance

Happy leap day, everyone. Use it wisely, it doesn't come around all that often.