I am trying to look at frequency distributions of results of medical tests. I
have downloaded many thousands of results for approximately 15 different
medical tests to an Excel file.

Following this, I have set up the frequency function to separate the data
into bins, and set up a list so that I can select one test at a time.

Unfortunately, I can't find any way to make the frequency function use just
the data displayed in my list, rather than all rows. Is there any way to
achieve what I want to do?

Many thanks.