502. If, at a particular time after 1971, a dividend becomes payable by a private corporation on a share of its capital stock and the corporation makes an election, at the latest at the particular time or, if it is earlier, on the day on which a portion of the dividend was paid, the following rules apply:(a) the dividend is deemed a capital dividend to the extent of its capital dividend account immediately before the particular time; and
(b) no portion of the dividend shall be included in computing the income of a shareholder of the corporation.