Hello!   I'm trying to count, how many times in total did the respondents answer a question X during the longitudinal study. I would like to have a mean and standard deviation.   Example: NAME           QUESTION X                   QUESTION X              QUESTION X                         AT POINT 1                   AT POINT 2                    AT POINT 3 Matt                       3                                         2                                     1           (three times)      Lisa                       4                                                                                4            (two times) Anne                                                                3                                      2           (two times) Karl                       3                                                                                              (one time)   I would like to know how many times in total (mean and SD) the participants provided information on the question X? In the example, I can see that the mean is 2, but I don't know how to make the script in SAS.   Thank you so much for your help! ... View more