Restoring Value to Minimum Variance

Abstract

A long-only investable minimum variance strategy outperformed the S&P 500 over the four decades from January 1973 to December 2012. Through the lens of a factor model, we show this outperformance can be largely attributed to implicit style bets. Specifically, minimum variance has thrived by tilting away from size and volatility and toward value. As funds have poured into minimum variance in the wake of the financial crisis, and plausibly as a consequence of this trend, the value tilt has disappeared and a momentum tilt has emerged. This suggests that the cost of entry to minimum variance is at an historic high. We show how the value tilt can be restored to minimum variance by targeting specific exposures, and that there was a substantial long-term benefit to the restoration at most recent points of entry to the strategy.

Keywords: minimum variance, low risk, value factor

JEL Classification: G11, G12