Index-Linked Investing—A Curse for the Stability of Financial Markets around the Globe?

Abstract

The authors analyze the development of various risk commonalities in Europe and the United States, as well as in emerging markets, and find a substantial increase in the co-movements in trading patterns, price returns, and liquidity risk within equity markets. They test the hypothesis that index-linked investing is a major driver for the increase in risk commonality. By aggregating the data in a cross-regional perspective, the authors capitalize on the different levels of indexation in the markets and find statistically significant and economically relevant evidence that the growth in index-linked investing is related to the increased co-movement within equity markets. The results suggest a significant increase in market fragility around the globe, leading to an increased danger of more severe reactions to unanticipated events going forward. Portfolio managers are well-advised to account for the increased proportion of index-linked investing within their risk management tools, diversification approaches, and active management strategies.