Is a pure TIPS strategy truly risk free?

A Treasury Inflation-Protected Security (TIPS) is virtually risk free. As an obligation of the U.S. Treasury, it is mostly free of default risk. As an inflation-indexed security held to maturity, it is risk free in terms of purchasing power. However, investing in a TIPS-only portfolio for retirement is not risk free. This paper presents the results of a simulation analysis designed to evaluate the performance of a portfolio of inflation-indexed Treasury coupon bonds. This study demonstrates that significant shortfall risk exists for TIPS-only portfolios across a range of savings plans and the securities selection rules.