In the course of the week, CME stock had fallen 42%.

The Prague Stock Exchange fell to its lowest level since Czech entry into the European Union. On Friday, it dropped 11.7%, the second largest one-day decline in its history. Since peaking in October 2007, the Prague Stock Exchange Index has fallen 60%.

The drop comes on the heels of a fall in the value of the crown against the dollar of over 30%, most of that within the past week. As recently as last month, the Czech Crown was vaunted as the strongest currency in the world.