Hi there,   I have weekly return data for each company, I would like to write a SAS code that can take the mean of the weekly returns for each company in the dataset.    My data looks like:   DATE                              COMPANY                                       RETURN 5/2/2014                         A                                                       0.01 12/2/2014                       A                                                       -0.05 19/2/2014                       A                                                       0.02 .......                                5/2/2014                         B                                                        0.02 12/2/2014                       B                                                        0.01 19/2/2014                       B                                                        -0.01 .........     After deducing the mean, I would also like to deduce standard deviation of returns for each company and seeing if any of the returns for each company are < 3.09 standard deviations in which case I would like insert a CRASH dummy variable of "1" for that company during that year, otherwise "0" .   Any help or ideas will be greatly appreciated.   Thanks. ... View more