Vincent Geloso and Chandler Reilly have a new paper in which they use Rothbard's "Private Product Remaining" (PPR) as a lower bound on estimates of national output, to be contrasted with the convention GDP statistics as an upper bound. Bob has the authors explain Rothbard's proposal and how they are trying to introduce it to the economics profession.
The Paper, "National Output Without Government?": https://Mises.org/HAP503a
The Human Action Podcast Episode on Dubious Origins of GDP/GNP: https://Mises.org/HAP503b
The Bob Murphy Show Episode With Alex Salter Criticizing "State Capacity": https://Mises.org/HAP503c