Economy of North Korea
Estimating gross national product in North Korea is a difficult task because of a dearth of economic data and the problem of choosing an appropriate rate of exchange for the North Korean won, the nonconvertible North Korean currency. The South Korean government's estimate placed North Korea's GNP in 1991 at US$22.9 billion, or US$1,038 per capita. In contrast, South Korea posted US$237.9 billion of GNP and a per capita income of US$5,569 in 1991. North Korea's GNP in 1991 showed a 5.2% decline from 1989, and preliminary indications were that the decline would continue. South Korea's GNP, by contrast, expanded by 9.3% and 8.4%, respectively, in 1990 and 1991.
Superdollar
It has been confirmed that North Korea has passed off superdollars (Korean: "kattalio") in various countries. The counterfeit bills also circulate both within North Korea and around its border with China. There is, however, some doubt about the reliability of North Korean defectors' claims, on which the United States partially bases its accusations, along with South Korean intelligence sources.