Any association may reduce its capital stock to any sum not less than the amount required to authorize the formation of any association by vote of its shareholders owning two-thirds of its stock. No such reduction may be made, however, until the amount thereof proposed is reported to the state banking board and its approval in writing obtained. No such reduction may affect the liability of shareholders for any debts of the association incurred prior to the reduction, and every such reduction must be certified to and a copy of the certificate filed in the same manner as for an increase of capital stock before it becomes valid.
N.D.C.C. § 6-03-24