The VARSTOCASES command
The below can also be performed using the RESTRUCTURE command under the DATA menu in SPSS. For the example below we wish to stack columns x and y to make a single column called time. This is particularly useful for converting data from a format suitable for repeated measures to one suitable for multilevel modelling in SPSS.
DATA LIST FREE / idno x y . BEGIN DATA 001 34 56 002 23 45 003 39 41 004 33 11 005 87 57 006 99 36 END DATA. SORT CASES BY IDNO. VARSTOCASES /MAKE time FROM x y /INDEX = newfact "new var label" (time) /KEEP = idno.