WHEN it became an independent nation in the seventeenth century, the Netherlands pioneered what today would be called austerity chic: think of the plain interiors painted by Vermeer or ruddy-faced merchants in their black smocks by Frans Hals. Today's chart, which shows a correlation between Christmas spending (culled from various sources) and wealth (in purchasing-power parity terms), suggests that the disapproval of those Amsterdam merchants still has some sway over their descendants. Lightly-taxed Luxemborgers, by contrast, are exceedingly generous outliers. Footloose readers would be well advised to head there for December 25th.