Text and Data Mining valid from 2019-04-08
Received: 25 April 2018
Accepted: 1 April 2019
First Online: 8 April 2019
Compliance with ethical standards
: The authors have no conflict of interest, ethics issues, or funding to report.
: The views expressed in this paper are solely those of the authors and not necessarily those of the U.S. Bureau of Economic Analysis or the U.S. Department of Commerce.