This macro can be used along with a CUSUM chart to estimate the size of a small, sustained shift in a process mean. This shift size is also expressed in terms of the within-subgroup sigma estimate.
Be sure that Minitab knows where to find your downloaded macro. Choose . Under Macro location browse to the location where you save macro files.
If you use an older web browser, when you click the Download button, the file may open in Quicktime, which shares the .mac file extension with Minitab macros. To save the macro, right-click the Download button and choose Save target as.
Suppose your data are in C2, the subgroup size is 5, and the target is 25. You suspect that there is a process shift that starts in subgroup 19 and ends at subgroup 30. To run the macro, choose and type:
%SHIFTSIZE C2 5 25 19 30
Click Run.