Korean yen
The Korean yen was the currency of Korea between 1910 and 1945. It was equivalent to the Japanese yen and consisted of Japanese currency and banknotes issued specifically for Korea. The yen was subdivided into 100 sen. It replaced the Korean won at par and was replaced by the South Korean won and the North Korean won at par.
Economy of North Korea
North Korea had a similar GDP per capita to its neighbor South Korea from the aftermath of the Korean War until the mid-1970s, but had a GDP per capita of less than $2,000 in the late 1990s and early 21st century.