; and (ii) the amount, as determined by the Academy, that when applied under the Program, protects insurers from insolvency in the case of covered event of such type of a severity equal to or exceeding that of a covered event of such type having a two percent chance of occurring in any given year. (C) Revision The agreement pursuant to subparagraph (A) shall provide for the Academy to review and revise the proposed trigger amounts for each participating State not less frequently than once every 24 months, and more frequently at the request of the Secretary. Any revised trigger amount may not take effect under the Program before the expiration of the 180-day period beginning upon the provision by the Secretary to such participating State of written notification of such revised trigger amount. (D) Assessment of insured losses The agreement pursuant to subparagraph (A) shall provide that following the occurrence of a covered event, the Academy shall, for each participating State affected, make assessments of the insured losses for each such State and provide such information to the Secretary. Such assessments shall be made on an ongoing basis as necessary to make an accurate determination of such insured losses. (E) Experts (i) Authority The agreement pursuant to subparagraph (A) shall provide that, in establishing proposed trigger amounts under this paragraph and assessing insured losses pursuant to subparagraph (D), the Academy may contract with such experts and consultants, including experts in disaster modeling, as it considers appropriate. (ii) Authorization of appropriations There is authorized to be appropriated to the National Academy of Sciences such sums as may be necessary for costs of hiring experts and consultants pursuant to clause (i). (3) Authority to issue bonds to fund Federal payments (A) Issuance In connection with a covered event for which the Secretary is required to make a payment under paragraph (1) to a participating State, the Secretary shall issue bonds under this paragraph, the proceeds