I stumbled on the answer. The subtotal option shows up when I "quickzoom" on a report but I seem to recall that this showed up in my old version anytime I did an easyreport. For example if I go to "reports and graphs" and select "How much did I spend on ...?" and then choose "Charity" for the show spending, I get a report of all the charity contributions and can sort them by name but the "customize" and "option" choices do NOT include "subtotal by...". On the other hand, if I select "Where did I spend my money during the period. . .?" and hit "show report", a list of everything shows up on the report. Then, doubleclicking the line item "charitable donations" pops up a "quickzoom report". When I hit the "customize" button for that report I then get the "subtotal" option.
I believe the previous version I was using (2000) had the subtotal option always present.