The Impact of Credit Rating Change on Investor Sentiment

The behavioral finance literature focuses on the effect of investor sentiment on the fundamental values of individual stocks. This study constructs a firm-level investor sentiment indicator based on transaction and price data for individual firms and shows that credit rating changes affect investor sentiment. We find the following empirical results. First, the response of investor sentiment to upgrades (downgrades) is significantly positive (negative). Second, the greater the magnitude of the downgrade is, the more negative the investor sentiment reaction is, although we do not find a similar result for upgrades. Third, cumulative abnormal returns around the event day are affected by cumulative abnormal sentiment before that day. This result suggests that the market reaction is affected by a combination of credit rating downgrades and investor sentiment.