Thanks for the reply and question.
I scrolled through the list of sets by year and noted each Pirates card for that year that had more than "1" for quantity. If it was a "2" for a card then that was 1 duplicate; if a "3" then it was 2 and so on. I made a list of the number of duplicates per card/per year. And I manually checked each card in my collection so as to confirm that indeed I had the quantity of duplicates as indicated in the database. That total turned out to be 76.
Now, is there any chance a card that has two Pirates on it (a league leaders, for instance) that I have one duplicate of is causing a discrepancy in the "counting" issue?
I appreciate any assistance.