Private non-profit expenditure on R&D (PNPERD) represents the component of GERD incurred by units belonging to the Private non-profit sector (see the definition of Private non-profit sector). It is the measure of intramural R&D expenditures within the Private non-profit sector during a specific reference period.
R&D surveys.
OECD (2015), Frascati Manual 2015: Guidelines for Collecting and Reporting Data on Research and Experimental Development.