隱含流動性溢酬於退休給付選擇之研究

Abstract

為因應人口老化及少子化趨勢所帶來之長期經濟生活保障問題，政府於98年1月1日施行新制勞工保險，將年金給付納入保險制度。對於98年1月1日前有勞保年資且年資達十五年以上之勞工，於退休時可選擇舊制下的一次請領老年給付或是新制的老年年金給付。因此，需探討以一次請領或年金給付方式何者對勞工較為有利。本研究以流動性與內部報酬率之角度來分析探討勞工保險新制下一次給付與年金給付之差異，比較年金給付理論上須提供之流動性溢酬(liquidity premium)與勞保新制下年金給付實際上所提供的內部報酬率(隱含長壽收益，ILY)，以提供退休勞工選擇之參考。研究結果發現，在1.5到3的風險趨避係數之間，無論投保年資、平均月投保薪資與性別，年金給付之隱含長壽收益扣除無風險利率後皆高於所應提供之流動性溢酬，比例大約在2到38.9。其中最低投保年資十五年之ILY最高(1,984~2,633 b.p.)，之後隨年資遞減，年資超過三十年以上之ILY又開始遞增。在投保年資二十年以下，最低投保薪資提供較高的ILY。比較男性與女性之差異，女性之流動性溢酬與ILY皆高於男性。由以上結果顯示，勞工於退休時選擇請領老年年金給付方式較佳。

In order to build up a complete Labor Insurance pension protection system and offer the insured person or insured person’s dependents long term living care, the system has added pension benefits on January 1, 2009. After the implementation of Labor Insurance pension program, the insured that has insurance coverage before January 1, 2009 could select the old-age one-time benefit or monthly pension benefit when they retire. Therefore, which benefit approach is better is an important concern for retiree. In this study, we take the concept of the liquidity premium and the implied longevity yield (ILY) to compare the old-age one-time benefit and pension benefit. The results show the ILY minus the risk-free rate would greater than the liquidity premium no matter what the insurance coverage years, insurance salary, gender, and the coefficient of relative risk aversion from 1.5 to 3, the ratio of the ILY to liquidity premium is about 2 to 38.9. Second, the insured with 15 coverage years has highest ILY (1,984~2,633 b.p.). Then the insured with lowest insurance salary and less than 20 coverage years could earn the highest ILY. Finally, the results indicate the female have higher ILY from annuitized pension benefit than the male. Overall, we find out that the implied longevity yield is higher than the liquidity premium under the old-age pension benefit. It would encourage insured to choose the old-age pension benefit when he/she retires.