N.D. Cent. Code § 6-03-34

The board of directors of any association organized under this title may declare and pay dividends out of the net profits of the association subject to the limitations of this chapter. Except for cooperative financial institutions, every such association, as its board of directors deems advisable, shall ascertain, set apart, and convert into a surplus fund at least fifty percent of its net earnings until such surplus fund equals one hundred percent of its common stock, and no dividend may be declared upon its stock except from the remaining fifty percent of its net earnings.