In determining need for assistance to the aged, blind, or disabled, the Department of Health and Human Services shall take into consideration all other income and resources of the individual claiming such assistance, as well as any expenses reasonably attributable to the earning of any such income, except as otherwise provided in this section. In making such determination with respect to any individual who is blind, there shall be disregarded the first eighty-five dollars per month of earned income plus one-half of earned income in excess of eighty-five dollars per month and, for a period not in excess of twelve months, such additional amounts of other income and resources, in the case of an individual who has an approved plan for achieving self-support, as may be necessary for the fulfillment of such plan. In making such determination with respect to an individual who has attained age sixty-five, or who is permanently and totally disabled, and is claiming aid to the aged, blind, or disabled, the department shall disregard earned income at least to the extent such income was disregarded on January 1, 1972, as provided in 42 U.S.C. § 1396a(f).