On December 12, 2019, Fed in Print will introduce its new platform for discovering content. Please direct your questions to Anna Oates

Home About Latest Browse RSS Advanced Search

Federal Reserve Bank of New York
Staff Reports
Is there an S&P 500 index effect?
Maria Kasch
Asani Sarkar

We find that the firms included in the S&P 500 index are characterized by large increases in earnings, appreciation in market value, and positive price momentum in the period preceding their index inclusion. This strong preinclusion performance predicts 1) the permanent increase of market value and 2) the change in return comovement, reflected in declines of size, value, and momentum betas, following index inclusion. Nonevent firms with similar performance experience similar appreciation in value and changes in comovement coincident with the event firms. Contrary to the consensus in the literature, our results indicate that—after accounting for the firms’ extraordinary preinclusion performance—index inclusion has no permanent effect on value and comovement.

Download Full text
Download Full text
Cite this item
Maria Kasch & Asani Sarkar, Is there an S&P 500 index effect?, Federal Reserve Bank of New York, Staff Reports 484, 2011, revised 01 Nov 2012.
More from this series
Note: Previous title: Comovement Revisited
JEL Classification:
Subject headings:
Keywords: Stock market; Risk; Index numbers (Economics)
For corrections, contact Amy Farber ()
Fed-in-Print is the central catalog of publications within the Federal Reserve System. It is managed and hosted by the Economic Research Division, Federal Reserve Bank of St. Louis.

Privacy Legal