When used in this article, unless the context clearly requires a different meaning:
(1) "Claimant" means a person sixty-five years of age or older who was domiciled in this state during any portion of the calendar year preceding the year in which the claimant is eligible to file a claim for relief under this article and who had a gross household income of not more than $5,000 during the calendar year preceding the year in which he is eligible to file a claim for relief under this article. If two or more individuals, who otherwise qualify as claimants under this article, occupy a single homestead, such individuals may determine between themselves as to which individual shall be the claimant; however, if such individuals are unable to agree, the matters shall be referred to the State Tax Commissioner for determination and his decision shall be final.