Discretionary Decision-Making and the S&P 500 Index

Discretion is an integral part of how indices, including stock market indices, are constituted, according to professors Rauterberg and Verstein and Robertson (here and here), and the S&P 500 index is no exception.

The S&P 500 is a market-weighted compilation of the share prices of common stock issued by 500 companies that are considered to represent blue-chip America. It is governed by the S&P’s U.S. Index Committee (“Committee”), which has almost total discretion in determining the companies that constitute the S&P 500.

In our new article, we find that the Committee’s discretionary decision-making has resulted in the … Read more