This subpart D sets forth basic guidelines for establishing the amount of monthly benefits payable to an eligible individual or couple (as defined in § 416.120(c)(5)). This subpart does not contain provisions with respect to establishing the amount of State supplementary payments payable in accordance with an agreement entered into between a State and the Administration under the provisions of subpart T of this part. Provisions with respect to determination and payment of State supplementary payments under such agreements will be administered by the Administration in accordance with the terms set forth in such agreements.