The balance of net income of an association, if any, may be credited to a surplus account from which the board of directors of any association with permanent capital stock may, at its discretion and at such times as it may determine, declare and pay dividends in cash or additional stock to the holders of record of the stock outstanding at the date the dividends are declared. The reserve fund shall, at all times, be maintained at not less than the minimum amounts required in the Savings and Loan Act.