Benefit increase means any benefit arising from the adoption of a new plan or an increase in the value of benefits payable arising from an amendment to an existing plan. Such increases include, but are not limited to, a scheduled increase in benefits under a plan or plan amendment, such as a cost-of-living increase, and any change in plan provisions which advances a participant's or beneficiary's entitlement to a benefit, such as liberalized participation requirements or vesting schedules, reductions in the normal or early retirement age under a plan, an unpredictable contingent event benefit, and changes in the form of benefit payments. In the case of a plan under which the amount of benefits depends on the participant's salary and the participant receives a salary increase the resulting increase in benefits to which the participant becomes entitled will not, for the purpose of this part, be treated as a benefit increase. Similarly, in the case of a plan under which the amount of benefits depends on the participant's age or service, and the participant becomes entitled to increased benefits solely because of advancement in age or service, the increased benefits to which the participant becomes entitled will not, for the purpose of this part, be treated as a benefit increase.
29 CFR § 4022.2
The following terms are defined in 4001.2 of this chapter: annuity, bankruptcy filing date, Code, employer, ERISA, guaranteed benefit, mandatory employee contributions, nonforfeitable benefit, non-PPA 2006 bankruptcy termination, normal retirement age, notice of intent to terminate, PBGC, person, plan, plan administrator, plan year, PPA 2006 bankruptcy termination, proposed termination date, statutory hybrid plan, substantial owner, and title IV benefit.