Hi all,   I am trying to run a proc panel data model but I am encountering a problem. Here is the code I have right now:   data have; input ID date indepvar depvar; datalines; 10001 02-02-2017 100 87 10001 02-06-2017 80 87 10001 02-08-2017 110  88 10002 02-05-2017 70 67 10002 02-08-2017 90 68 10002 02-011-2017 140 68 ; run; proc panel data = have; id ID date; model indepvar = depvar / FIXTWO; run;   When I run the above regression, I get the error: There is only one cross section or time series observation. Computations will be terminated   There are no missing values in any of the variables and I have only selected date values with ≥2 observations.   I have searched this forum and there are others who have encountered this problem, but none of the solutions given solved the error. How should I arrange my data for the proc panel so that I do not face the above error?   Thanks in advance ... View more