; (II) explains that the actual payments under the lifetime income stream described in clause (i)(III) that may be purchased with the total benefits accrued will depend on numerous factors and may vary substantially from the lifetime income stream equivalent in the disclosures; (III) explains the assumptions upon which the lifetime income stream equivalent was determined; and (IV) provides such other similar explanations as the Secretary considers appropriate. (iii) Assumptions and rules Not later than 1 year after the date of the enactment of the Lifetime Income Disclosure Act , the Secretary shall— (I) prescribe assumptions that administrators of individual account plans may use in converting total accrued benefits into lifetime income stream equivalents for purposes of this subparagraph