The screenshots now show the whole page rather than a cropped viewport, and the
configuration table is included so the three variables in the grid can be
traced to the three rows that define them.
Three screenshots from the EDIT screen: the derived columns in the grid, a
filter on a character derived column, and a filter on a numeric one. Plus a
short 'how it works' explaining that the statements go into a DATA step view
because a WHERE cannot see a variable created in the same step.