1. RGS Econ and RWI – Leibniz-Institute for Economic Research , Hohenzollernstr. 1-3, 45128 Essen , Germany
2. RWI – Leibniz-Institute for Economic Research , Hohenzollernstr. 1-3, 45128 Essen , Germany
3. University of Cologne, Center for Macroeconomic Research (CMR) , Albertus-Magnus-Platz, 50923 Cologne , Germany
4. RWI – Leibniz-Institut for Economic Research , Hohenzollernstr. 1-3, 45128 Essen , Germany