Not sure if this is all providence or just their system. Let me know if I can provide further details. Basically when they search on Collection it says that they have more collection records than they actually have (it includes all records in the summary, Series, Subseries and so on)
By default the browse is automatically expanding the result set to include subtypes. So the final result includes both fonds and series. I’ve set the dontExpandHierarchically option on the collection “type” facet in browse.conf to disable this behavior, so the result count is now 806 (what is displayed now – not 805).