Tobias Hagen Frankfurt University of Applied Sciences   Frankfurt University of Applied Sciences Department of Business and Law Nibelungenplatz 1 Frankfurt, Hessen 60318 Germany   tobiashagen@email.de   https://www.fh-frankfurt.de/de/fachbereiche/fb3/ansprechpartner_innen/professoren_innen/hagen.html           JEL Areas: E3 : Prices, Business Fluctuations, and Cycles: General (includes Measurement and Data) C2 : Single Equation Models; Single Variables: General