This macro calculates the first and third quartiles using the counting method found in many textbooks, as opposed to the percentile method used in Minitab.
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 column C1 contains the data. To run the macro, choose and type:
%QRTILES C1
Click Run.