In actuarial valuations, one of the fundamental objectives is the minimization of actuarial Gains and Losses, in order to impact as little as possible the equity account in OCI, (OTHER COMPREHENSIVE INCOME STATEMENT). Under IAS 19, actuarial gains/losses cannot be amortized over the average future working life of the population. Minimizing losses is not an easy task, given, among other things, the uncertainty of the expected benefits to be paid, discount rates and salary increases, as well as staff turnover rates. In this paper, the Actuarial Gain / Loss (G/P) is modeled when salary increase rates vary as a decision variable that in some way affects the Actuarial Liabilities of the fiscal year (PBO) and therefore the next year annual cost.