In the Fall 2012 electronic edition of The Journal of Art Crime, authors Ruth Judson and Richard Porter write of "Estimating the Volume of Counterfeit U.S. Currency in Circulation Worldwide: Data and Extrapolation":
The incidence of currency counterfeiting and the possible total stock of counterfeits in circulation are popular topics of speculation and discussion in the press and are of substantial practical interest to the U. S. Treasury and the U. S. Secret Service. This paper assembles data from Federal Reserve and U. S. Secret Service sources and presents a range of estimates for the number of counterfeits in circulation. In addition, the paper presents figures on counterfeit passing activity by denomination, location, and method of production. The paper has two main conclusions: first, the stock of counterfeits in the world as a whole is likely on the order of 1 or fewer per 10,000 genuine notes in both piece and value terms; second, losses to the U. S. public from the most commonly used note, the $20, are relatively small, and are miniscule when counterfeit notes of reasonable quality are considered.
Dr. Judson is an economist in the Division of International Finance at the Board of Governors of the Federal Reserve System in Washington, D. C. She holds an A. B. in Russian Civilization from the University of Chicago and a PhD in economics from the Massachusetts Institute of Technology. Her research and policy work is wide-ranging, and has addressed topics in cross-country growth, panel data estimation methods, monetary policy implementation, the monetary aggregates, and the measurement and analysis of U. S. dollar usage outside the United States, and, most recently, cross-border capital flows. Along with Richard Porter, she received a certificate of appreciation in special recognition of efforts and superior contributions for the International Currency Audit Program (ICAP) to the law enforcement responsibilities of the United States Secret Service in 2000. The analysis in this article grew out of work on the ICAP.
Richard Porter is a vice president and senior research advisor, payments in the economic research department of the Federal Reserve Bank of Chicago. Before joining the Bank, Porter served as an economist at the Board of Governors of the Federal Reserve System for over three decades, most recently as a senior adviser in the Division of Monetary Affairs. Prior to that, Porter was an assistant professor of economics at Ohio State University.
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