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A sample packaged workbook (twbx) would help us help you.
That said, in order to show values where none exist (i.e. count zero when there is nothing), the option "show missing values" can do it, but frequently you may need a "scaffold," which is a data set that includes all the values you need in order to measure the occurrences for that value.
Again, a packaged workbook with an example would help.