The Impact of Interim Earnings Announcements on the Permanent Price Effects of Trades on the Helsinki Stock Exchange

Abstract

The primary goal of this paper is to study whether the permanent price impact of large trades are greater before or after an interim earnings announcement on the Helsinki Stock Exchange. If the permanent price effects of large trades are greater before the announcement this would suggest that investors believe that some traders are better informed before the interim earnings announcement than after. Theoretical support is available that information asymmetry is greater prior to earnings announcements than after. The anticipation of a forthcoming public announcement stimulates the acquisition of private information, causing an increase in information asymmetry. This increase is facilitated by the flow of earnings-related information to the market (e.g., via pre-announcement communications by firms, actual earnings announcements of competitors, etc.). Thus investors gather information, make assessments, and form trading positions accordingly. In addition, compared to individuals (small investors), institutions (large investors) are better informed because they tend to have lower marginal costs of information gathering. Thus large trades are expected be monitored more closely on the trading screen and the information content for pricing purposes is expected to be larger for these trades than for corresponding small trades. Using permanent price effects as a measure of price adjustment for private information, tests were performed to see whether price adjustments are greater in pre-announcement periods than in post-announcement periods. The results, based on interim earnings releases, suggest that large trades do indeed produce greater permanent price effects before an announcement than after it. This suggests that large trades associated with price changes (especially uptick trades) before an announcement send a stronger signal to other investors than similar trades after the announcement. For small trades the results were insignificant.

Note: This is a description of the paper and not the actual abstract.

JEL Classification: D82, G14, M41