Lev started it's history in 1880 when an independent Bulgarian state appeared. In 1947 there was a post-war monetary reform, new leva banknotes were exchanged at 1:1 ratio, new reform took place in 1952 (1:100), and another one in 1962 (1:10). After a period of inflation in 1990ies, new lev, tied to the german mark, was introduced. Upon the introduction of the euro, lev's exchange rate was tied to the euro.