The net stable funding ratio is a liquidity standard requiring banks to hold enough stable funding to cover the duration of their long-term assets. For both funding and assets, long-term is mainly defined as more than one year, with lower requirements applying to anything between six months and a year to avoid a cliff-edge effect. Banks must maintain a ratio of 100% to satisfy the requirement. Introduced as part of the post-crisis banking reforms known as Basel III, the ratio ensures banks do not undertake excessive maturity transformation, which is the practice of using short-term funding to meet long-term liabilities. It was finalised by the Basel Committee in October 2014.