Young Men’s Christian Association.

All property belonging to the Young Men’s Christian Association of the District of Columbia, used and occupied by that Association, shall, so long as the same is so owned and occupied, be exempt from taxation, national and municipal; provided, that where ground of said Association is larger than is reasonably required for its use, or is not actually used for the legitimate purposes of said Association, or if said ground or buildings shall be used for private gain, such portion of said ground or buildings as shall not actually be used for the purposes of said Association, or from which it derives a rent or income, such portion of the same, or a sum equal in value to such portion, shall be taxed against such Association.