How Sub-Optimal Are Age-Based Life-Cycle Investment Products?

Abstract

We investigate the conditions under which life-cycle investment strategies based on age may be ‘near enough’ to optimal, focusing on the treatment of the pension account balance and assumptions about risk aversion. We show that dynamically adjusting the strategy in response to fluctuations in the balance as well as age can lead to moderate improvements over product designs currently seen in the market; although most of the potential gains might be captured by specifying the glide path with reference to a measure of expected value of the balance over time. The risk aversion assumption emerges as a far more important consideration, with much greater utility losses arising from mismatches between the risk aversion of the investor and that underpinning the glide path design. Our analysis points towards possibilities for improving life-cycle or target date funds, and highlights the benefit of offering a suite of such funds that cater for members with differing risk aversion.

Keywords: life-cycle models, portfolio optimization, investment product design, target date funds

JEL Classification: C61, C63, G11, G23