"To receive this benefit (Fed Deposit Insurance), member banks must follow certain liquidity and reserve requirements. Banks are classified into five groups according to their risk-based capital ratio:
Well capitalized: 10% or higher
Adequately capitalized: 8% or higher
Undercapitalized: less than 8%
Significantly undercapitalized: less than 6%
Critically undercapitalized: less than 2%
When a bank becomes undercapitalized the FDIC issues a warning to the bank. When the number drops below 6% the FDIC can change management and force the bank to take other corrective action. When the bank becomes critically undercapitalized the FDIC declares the bank insolvent and can take over management of the bank."