International Investment for Retirement Savers: Historical Evidence on Risk and Returns

An important decision facing retirement savers is how to allocate their savings across different assets. The decision includes the choice of how to divide investments between domestic and foreign holdings. This study uses return data for 1927-2005 to determine whether cross-border investing in the past would have been advantageous to retirement savers in eight large industrialized countries. By assumption investors can buy mutual fund shares in index funds for stocks and bonds in their home country and in any of seven foreign countries. The mutual funds’ foreign holdings are not hedged to protect investors against currency fluctuations. The paper’s goal is to determine whether workers in the eight countries would have obtained higher expected retirement incomes, with smaller risk of catastrophic investment shortfalls, if they invested part of their retirement savings in foreign stocks and bonds. Consistent with past theoretical and empirical findings, the results show that workers could have improved expected financial performance by investing in foreign as well as domestic equities. Remarkably, retirement savers in nearly all countries would have obtained higher average pensions with a 100% foreign allocation than with a 100% domestic allocation, even if they followed extremely naïve strategies in allocating equity investments across different foreign markets. For retirement savers in most countries, though not the United States, naïve overseas investment strategies would also have reduced the risk of catastrophically poor investment performance. In all countries, retirement savers who selected a global portfolio allocation along the efficient frontier could obtain better average pensions with lower risk of very small pensions than savers who restrict their investments to the domestic stock and bond funds.