Corporate managers can share information about the financial status and corporate future perspective with stockholders in different ways. In recent years, the corporate program for maximizing the appropriate reaction of Securities Exchange to corporate position performance and minimizing the inappropriate reaction to their negative performance has been considered by analysts and accounting researchers. In this research we use the multivariate regression model to test the hypotheses and our statistical population is Tehran stock Exchange corporate. After sampling, 64 corporates have been selected during 2014to 2018. And to test hypotheses Multivariate regression has been used According to the results obtained Managers change timing to hide The bad news is that they are using the stock market after hours after the stock market Managers while have made less use of the weekend and busy days to hide bad news The results also show that companies have used time changes to highlight good news rather than hide bad news So to investors and other users It is advisable to pay attention to the time changes of the forecast profit, to make a more correct decision.
