Optimal Consumption, Investment and Housing with Means-tested Public Pension in Retirement

TL;DR

This paper models Australian retirees' optimal consumption, housing, and investment decisions considering means-tested pensions, mortality risk, and health, revealing how policies influence retirement behavior and asset allocation.

Contribution

It introduces a numerical stochastic control model for retirement decumulation that incorporates means-tested pensions, health proxies, and empirical calibration, providing new insights into retiree decision-making.

Findings

Optimal policy sensitivity to Age Pension decreases with age.

Risky asset allocation increases as wealth decreases due to pension buffering.

Couples are more aggressive in risky investments than singles.

Abstract

In this paper, we develop an expected utility model for the retirement behavior in the decumulation phase of Australian retirees with sequential family status subject to consumption, housing, investment, bequest and government provided means-tested Age Pension. We account for mortality risk and risky investment assets, and introduce a health proxy to capture the decreasing level of consumption for older retirees. Then we find optimal housing at retirement, and optimal consumption and optimal risky asset allocation depending on age and wealth. The model is solved numerically as a stochastic control problem, and is calibrated using the maximum likelihood method on empirical data of consumption and housing from the Australian Bureau of Statistics 2009-2010 Survey. The model fits the characteristics of the data well to explain the behavior of Australian retirees. The key findings are the following: First, the optimal policy is highly sensitive to means-tested Age Pension early in retirement but this sensitivity fades with age. Secondly, the allocation to risky assets shows a complex relationship with the means-tested Age Pension that disappears once minimum withdrawal rules are enforced. As a general rule, when wealth decreases the proportion allocated to risky assets increases, due to the Age Pension working as a buffer against investment losses. Finally, couples can be more aggressive with risky allocations due to their longer life expectancy compared with singles.