Although central banks have directly released e-money previously - such as Finland's Avant stored value e-money card in the 1990s[8] - the present concept of "central bank digital currency" may have been partially inspired by Bitcoin and similar blockchain-based cryptocurrencies. It is also a known concept in the field of economics, whereby the central bank enables citizens to hold accounts with it, providing a reliable and safe public savings or payments medium ("retail" or "general-purpose" CBDC).