So, when in 1971 Europe was jettisoned from the dollar zone, and exchange rates between its currencies started bobbing up and down, some of them falling as violently as others were rising, the European Union had real trouble managing the heavy industry cartel and the common agricultural policy that were its core. Without stable steel, coal and agricultural prices across France, Germany, Belgium, the Netherlands and Italy, cartel-like price fixing was impossible. [...]
and of course that was the main purpose of the EU (well, its precursor) at the time