12 CFR 217.144 – Simplified supervisory formula approach (SSFA)
(a) General requirements for the SSFA. To use the SSFA to determine the risk weight for a securitization exposure, a Board-regulated institution must have data that enables it to assign accurately the parameters described in paragraph (b) of this section. Data used to assign the parameters described in paragraph (b) of this section must be the most currently available data; if the contracts governing the underlying exposures of the securitization require payments on a monthly or quarterly basis, the data used to assign the parameters described in paragraph (b) of this section must be no more than 91 calendar days old. A Board-regulated institution that does not have the appropriate data to assign the parameters described in paragraph (b) of this section must assign a risk weight of 1,250 percent to the exposure.
(b) SSFA parameters. To calculate the risk weight for a securitization exposure using the SSFA, a Board-regulated institution must have accurate information on the following five inputs to the SSFA calculation:
(1) K
(2) Parameter W is expressed as a decimal value between zero and one. Parameter W is the ratio of the sum of the dollar amounts of any underlying exposures of the securitization that meet any of the criteria as set forth in paragraphs (b)(2)(i) through (vi) of this section to the balance, measured in dollars, of underlying exposures:
(i) Ninety days or more past due;
(ii) Subject to a bankruptcy or insolvency proceeding;
(iii) In the process of foreclosure;
(iv) Held as real estate owned;
(v) Has contractually deferred payments for 90 days or more, other than principal or interest payments deferred on:
(A) Federally-guaranteed student loans, in accordance with the terms of those guarantee programs; or
(B) Consumer loans, including non-federally-guaranteed student loans, provided that such payments are deferred pursuant to provisions included in the contract at the time funds are disbursed that provide for period(s) of deferral that are not initiated based on changes in the creditworthiness of the borrower; or
(vi) Is in default.
(3) Parameter A is the attachment point for the exposure, which represents the threshold at which credit losses will first be allocated to the exposure. Except as provided in section 142(l) for n
(4) Parameter D is the detachment point for the exposure, which represents the threshold at which credit losses of principal allocated to the exposure would result in a total loss of principal. Except as provided in section 142(l) for n
(5) A supervisory calibration parameter, p, is equal to 0.5 for securitization exposures that are not resecuritization exposures and equal to 1.5 for resecuritization exposures.
(c) Mechanics of the SSFA. K
(1) When the detachment point, parameter D, for a securitization exposure is less than or equal to K
(2) When the attachment point, parameter A, for a securitization exposure is greater than or equal to K
(3) When A is less than K