Data published on OECD.Stats Extracts gives an overview of the absolute numbers of graduates from tertiary type-A and advanced research programs for all standard fields of education.  According to the International Standard Classification of Education (ISCED), economics and economic history fall under the category of Social and Behavioral Science (business and related disciplines are not included). The graph presented above includes aggregated data for countries with the largest number of graduates in social and behavioral science* for the year 2010. The number of graduates from the US significantly out numbers graduates from other OECD countries, leading in every other discipline as well. Unfortunately, there is no information available on the exact percentage of economists among the graduates.

*Social and Behavioral Science include: Economics, economic history, political science, sociology, demography, anthropology (except physical anthropology), ethnology, futurology, psychology, geography (except physical geography), peace and conflict studies, human rights.