Funding for this research was provided by:
Oesterreichische Nationalbank (14856)
Received: 25 February 2018
Revised: 2 July 2018
Accepted: 27 July 2018
First Online: 21 August 2018
Change Date: 14 July 2020
Change Type: Correction
Change Details: An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Compliance with ethical standards
: The authors declare that they have no conflict of interest.