You can enter the institution's low and high-risk rating codes on the Credit Rating Codes page.
When you select from the menu, the Credit Rating Codes page appears by default.
Defining the institution's low and high-risk rating codes allows current expected credit losses (CECL) results to be matched to financial institution-specific credit scores.

You can use single-letter codes or numeric values from 1 through 100, but you cannot mix alpha and numeric values.