A. Cost of living supplements shall be payable under this section if:
1. The combined disability benefit entitlement of a claimant or his dependents under this title and the federal Old-Age, Survivors, and Disability Insurance program is less than 80 percent of the average monthly earnings of the claimant before disability or death; or
2. The claimant or his dependents are receiving disability payments under this title but not benefits under the federal Old-Age, Survivors, and Disability Insurance program. Such cost of living supplements shall be payable, in addition to the other benefits payable under this title, in accordance with the provisions of this section to those recipients of awards resulting from occupational disease, accident, or death occurring on or after July 1, 1975, under § 65.2-500, subsection C of § 65.2-503, subdivision A 4 of § 65.2-504, and §§ 65.2-512 and 65.2-513. For purposes of determining the monthly amount of combined disability entitlement received by a claimant pursuant to subdivision A 1, the claimant may deduct any monthly amounts paid for Medicare.
B. The Commission may require the claimant to present evidence of filing for federal Old-Age, Survivors, and Disability Insurance benefits in order to establish eligibility under subdivision A 1 and also may require the claimant to furnish the employer with the decision on his claim for such federal benefits.
C. The amounts of supplementary payments provided for herein shall be determined by using a compounding method of computation annually. The percentage of change shall be determined by reference to the increase, if any, in the United States Average Consumer Price Index for all items, as published by the Bureau of Labor Statistics of the U.S. Department of Labor, from its monthly average, from one calendar year to another.
D. Amounts of supplementary payments shall be based on the percentage increase, if any, in the Average Consumer Price Index for all items adjusted annually. Any change in the cost of living supplement determined as of any determination date shall become effective as of October 1 next following such determination date and, as the case may be, shall be added to or subtracted from any cost of living supplements previously payable; however, compensation paid the claimant under this section shall at no time exceed the then current maximum weekly amount payable under § 65.2-500.