(a) Unless the context clearly indicates otherwise, when used in this division, "capital" for a savings association includes (as applicable) the amount of its issued and outstanding common stock, preferred stock (to the extent such preferred stock may be considered a part of the savings association's capital under GAAP) plus any retained earnings and additional paid-in capital as well as such other items as the Commissioner may approve in writing for inclusion as capital.(b) Minimum capital requirement. Each savings association must maintain capital at levels that are required for institutions whose accounts are insured by the FDIC.