The ruble (or rouble) (Russian: рубль, romanized: rublʹ, [ˈrublʲ] ; symbol: ₽; ISO code: RUB) is the official currency of the Russian Federation. Banknotes and coins are issued by the Central Bank of Russia, which is Russia's monetary authority independent of all other government bodies. Each ruble is technically subdivided into 100 kopeyka (kopecks), but kopeck-denominated coins are now rarely used due to inflation. It is the second-oldest currency in continuous use, after British sterling. It was also the first decimal currency. The ruble was the currency of the Russian Empire and later the Soviet Union, where it was known as the Soviet ruble (code: SUR, 810). Following the dissolution of the Soviet Union in 1991, the Soviet ruble was replaced in Russia with the Russian ruble (code: RUR, 810) at par in the following year. The Russian ruble continued to be used in 11 post-Soviet states, forming a "ruble zone" until 1993. In 1998, the ruble was redenominated (code: RUB, 643) shortly before the 1998 financial crisis, at a rate of 1000 RUR = 1 RUB. The ruble is a free-floating currency, and in 2023, the digital ruble was introduced. The Russian ruble is also used as a de facto legal tender in Baikonur, Abkhazia and South Ossetia.