精算盈虧
actuarial gains and losses
從產生的設定受益義務的現值的變化：（1）經驗調整（以前的精算假設和什麼實際發生之間差異的影響）; （二）精算假設變動的影響
The changes in the present value of the defined benefit obligation resulting from: (a) experience adjustments (the effects of differences between the previous actuarial assumptions and what has actually occurred); and (b) the effects of changes in actuarial assumptions