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.
Korean won
The won was introduced in 1902, replacing the yang at a rate of 1 won = 5 yang. Units: 1 won = 100 chon/銭, 1 chon = 5 poon/分(fun ec. yesteryear spellings) of the preceding currency. In 1909, the Bank of Korea (한국은행; 韓國銀行) was founded in Seoul as a central bank and began issuing currency of a modern type. The won was equivalent to the Japanese yen and was replaced by the Korean yen in 1910 during the Colonial Era. In 1910, the Bank of Korea was renamed the Bank of Joseon (; 朝鮮銀行), which issued notes denominated in yen and "sen".