The Billfold:
Short of some Die Hard with a Vengeance sort of scheme, bank robbers can only carry away so much money—whatever fits on their person, in their car, whatever. And because our currency inflates at a rate of about two percent per year, a bank robber’s haul decreases by that much in spending power every year, meaning that the burlap sack of loot clutched in John Dillinger’s palm was worth considerably more to him than the exact same assortment of bills would be in your hand, today.