|Source: Torsten Slok|
A section of macroeconomics holds that nominal wages are sticky, pretty much forever. Hence, countries like Greece need their own currencies so they can depreciate them. Somehow this didn't produce great prosperity the first, oh, 147 times Greece tried it, but anyway, it's common to bemoan how terrible it is for Greece to be part of the euro because wages can't fall and it can't depreciate.
Or not, as the graph shows.