Under the capital adequacy standards set for commercial banks by the Bank for International Settlements, at least half of the eight percent of capital required to be set against risk-weighted assets must be core capital (or tier one) This comprises equity and disclosed reserves (q.v.) So-called supplementary capital, or tier two, constitutes the rest. This includes undisclosed reserves, general provisions against loan losses, subordinated term debt and hybrid capital instruments combining characteristics of debt and equity.