A bank must record actual defaults on IRB exposure classes using this reference definition. A bank must also use the reference definition for its estimation of PDs, and (where relevant) LGDs and EADs. In arriving at these estimations, a bank may use external data available to it that is not itself consistent with that definition, subject to the requirements set out in paragraph CA-5.8.75. However, in such cases, banks must demonstrate to CBB that appropriate adjustments to the data have been made to achieve broad equivalence with the reference definition. This same condition would apply to any internal data used up to implementation of this Module. Internal data (including that pooled by banks) used in such estimates beyond the date of implementation of this Module must be consistent with the reference definition.