Any contract providing benefits payable in variable amounts delivered or issued for delivery in this state shall contain a statement of the essential features of the procedures to be followed by the insurer in determining the dollar amount of such variable benefits. Source: SL 1966, ch 111 , ch 6, § 36 (4) as added by SL 1967, ch 131 ; SDCL, § 58-28-4; SL 1971, ch 266 , § 2.