1. Any claimant who is not entitled to an increase pursuant to NRS 616C.465 and who receives less in disability benefits from the federal social security system and pursuant to chapters 616A to 616D, inclusive, of NRS, combined, than an amount equal to 80 percent of average current earnings established pursuant to section 224 of the Social Security Act, as amended (42 U.S.C. § 424a), is entitled to an increase in his or her compensation for a permanent total disability of:
(a) The increase provided pursuant to NRS 616C.465; or
(b) The difference between the amount of benefits the claimant is receiving and 80 percent of the average current earnings,
Ê whichever is less.
2. The increase provided by this section must not be paid for any period before July 1, 1981.