Hi Guys, I am trying to obtain the median value using median() function in PROC SQL  as follows (SAS9.4): /* select clause with additional columns: Name Height*/ proc sql; select Name,Sex,Height,median(Height) as Med_Height,mean(Height) as Mean_Height from sashelp.class group by sex having sex="M"; quit; The results are as follows: However,  when removing columns Name, Height in select clause like this: /* select clause without additional column */ proc sql; select Sex, median(Height) as Med_Height, mean(Height) as Mean_Height from sashelp.class group by sex having sex="M"; quit; The results are as follows: Comparing the two tables, the mean value of Height is still 63.91 while the median of Height changes from 64.3 to 64.15 (of course the 64.15 is the right value).   Where did the first median value 64.3 come from? How did this difference (64.3 v.s. 64.15) happen? After all the mean value remains the same. I feel confused. Can anyone explain this? Thanks a lot guys. Appreciate it.  ... View more