Holmes, "Supplemental Retirement Arrangements May Provide Deferral for Employee and Deduction for Employer", Taxation of Executive Compensation and Retirement, March 1990, p. 243

Where the amount of pension under a supplemental plan that is payable to an executive may not be ascertainable until the executive retires, it nonetheless may be known that the pension will not be less than an ascertained amount, in which event the employer may well be entitled to deduction to the extent that the pension is ascertained and the employer has an existing obligation to pay the ascertained amount.

Once the amount of payments to be made to an employee under a supplemental pension arrangement are determined, the accrual rules should not apply as long as the employer's obligation is not interest bearing - because the executive has no cost for his entitlement to the payments, and thus the calculation of deemed interest cannot be performed.