Plenty of material for an econometrician of Jorgenson's caliber to work with to derive base parameters for a retail sales tax as well as from numerous high rate single stage tax systems that have existed and been removed as EU and IMF imposed VATs were put in place.Are you suggesting Jorgenson used statistics from the EU or some other place to model the change to a NRST?
If so, prove it.
Experience with you has shown that nothing satifies any demand of proof by you, however
If ever you deign to look in the References section of his Barker NRST work [here ] you would know that he definitely does not restrict himself to purely US information, nor are his econometric research papers limited to the US.
Or better look in Jorgenson's Collected Works laying out the basis of his studies
And his list of sources:
http://post.economics.harvard.edu/faculty/jorgenson/colwork/econs1.pdf
for Econometrics Vol. 1
Econometric Modeling of Producer Behavior
And list of sources
http://post.economics.harvard.edu/faculty/jorgenson/colwork/welfares1.html
which amply demonstrate his familiarity and use of world wide information in developing submodules for his econometric models.