Earnings Announcements are Full of Surprises
37 Pages Posted: 19 Jun 2006 Last revised: 25 Feb 2008
Date Written: January 22, 2008
We study the drift in returns of portfolios formed on the basis of the stock price reaction around earnings announcements. The Earnings Announcement Return (EAR) captures the market reaction to unexpected information contained in the company's earnings release. Besides the actual earnings news, this includes unexpected information about sales, margins, investment, and other less tangible information communicated round the earnings announcement. A strategy that buys and sells companies sorted on EAR produces an average abnormal return of 7.55% per year, 1.3%more than a strategy based on the traditional measure of earnings surprise, SUE. The post earnings announcement drift for EAR strategy is stronger than post earnings announcement drift for SUE. More importantly, unlike SUE, the EAR strategy returns do not show a reversal after 3 quarters. The EAR and SUE strategies appear to be independent of each other. A strategy that exploits both pieces of information generates abnormal returns of about 12.5% on an annual basis.
Keywords: post-earnings announcement drift, market efficiency, under-reaction, non-earnings accounting information
JEL Classification: G12, G14
Suggested Citation: Suggested Citation