For defined benefit schemes entering the Pension Protection Fund, we use an approximation to model the potential decrease in benefits.
This approximation is to apply a proportion of 90% to the largest future starting final salary / Defined Benefit annual pension that is entered. We assume that only one person will enter the Pension Protection Fund, even in a joint life case.
This approach applies to both pre and post retirement defined benefit pensions starting in the future, and doesn't include the upper cap.