Personally, when it comes to marking Mexican historic anniversaries I prefer to celebrate heroic defeats against overwhelming odds, like April 30, the anniversary of the battle of Camaron, fought near Puebla nearly a year after the big battle. Camaron gave rise to some of the most enduring traditions of the French Foreign Legion. The siege of the Alamo also comes to mind.
At least I know what I'm celebrating, though, unlike certain presidents we might know:
Anyway, whatever you call it, enjoy the occasion. It's probably the only way to get rid of your Derby Day hangover, anyway.