Impact de la publication des notes financières sur les cours et les volume de transaction des sociétés cotées à la BRVM : Une analyse à partir des études d'évenement

The West African Regional Securities Exchange (BRVM) is the common financial center for eight countries of the West African Economic and Monetary Union (WAEMU). It began its activities on 18th September 1998 and has undergone significant changes over the last three years (continuous quotation, introduction of local rating agencies, etc.) which have certainly influenced its dynamics, perception and behavior actors. In this research, we study the impact of the publication of financial ratings on the price and liquidity of shares listed on the West African Regional Securities Exchange (BRVM). Indeed, since the first quarter of 2013, ratings are part of the public information disseminated at the BRVM to guide investors in their investment choices. This new feature is likely to reduce the information asymmetry between investors and securities issuers (equity) and likely to reduce the cost of capital. Thus, it is expected that the prices of stocks will be adjusted before, after or after the financial rating released. The speed of this adjustment depends on the information content of the news disseminated, the responsiveness of the players and the level of market efficiency. It is to shed light on the lessons that can be drawn from the change in the context of developing market that we conducted a research on the influence of the rating released the stock prices. It makes a contribution at three levels. First, from a theoretical point of view, it questions the validity of the conclusions of the asymmetry information theory on the dynamics and cost of capital in a developing market. Secondly, from the managerial point of view, it proposes a guidelines on the organization and development of a regional financial market compatible with the development challenges of the WAEMU countries and taking into account this new situation in Investment choices. Finally, it proposes an approach to conduct a specific event study in a market that is not very liquid.