Hope this is the right location!    I have some data I'm trying to run t-tests on, but have to get creative with backing into the data to get the SD. I have the frequency distribution and N sizes, but not individual level data. What I've done so far (in excel, since I don't know how in SAS) is multiply the N size by the percent that answered each question either a 1,2,3,4,or 5 to determine what # of people in each group responses a certain way to each question (Sheet 1) and then transposed it to the format I *THINK* SAS will want it in (Sheet 2). It looks something like this   Question_Answer Response Group_1 Group_2 Group_3 Q0A1 1 50 200 50 Q0A2 2 100 0 25 Q0A3 3 25 25 50 Q0A4 4 75 25 25 Q0A5 5 50 25 50 Q1A1 1 0 50 25 Q1A2 2 100 50 100 Q1A3 3 100 75 0 Q1A4 4 25 75 25 Q1A5 5 75 25 50   From here I need to get the standard deviation of each question for each group and am at a total loss of how to do that. I'm not sure if I should keep the Question column parsed out the way it is (Question 1 Answer 1, Question 1 Answer 2) or just repeat Question1 for five rows and let the response column do the heavy lifting.    Any help would be greatly appreciated!  ... View more