I found a way that worked. First, working in the gradebook, open to categories, I went to the bottom and clicked to set up a new grade item, "Count."
I returned to grade category view, found "Count," and clicked on the calculator symbol.
I went down the display of my graded items and added a number to each. Quizzes could then be referred to as 1, 2, etc.
Here's what I put in the formula box at the top:
=round((1/80)-0.49,0) + round((2/80)-0.49,0) + round((3/80)-0.49,0) + round((4/80)-0.49,0)
adding additional +round units until I had listed the number of every grade I wanted counted.
It took some fiddling to make sure the formula and the ID numbers were correct, but when they were correct, Moodle accepted the formula and it worked.
The formula above is set up to count each grade that is 80% or higher. Modify the 80 to whatever grade you need to count.