I would contest the hidden assumption/assertion in your comment that GDP per capita can be used to compare productivity. Especially averaged out across the enti

I would contest the hidden assumption/assertion in your comment that GDP per capita can be used to compare productivity. Especially averaged out across the entire economy disregarding wealth distribution. It is a given that GDP per capita is a measure of a country's economic output per person. I know that is the technical definition of GDP per capita. And presumably then you would link economic output to productivity. You've fudged together too many uncorrelated entities :)