             delete @_requestersByQs[deletedQss][computation._id]
             if _.isEmpty @_requestersByQs[deletedQss]
                 delete @_requestersByQs[deletedQss]
+                @_incChanges @parseQs(deletedQss).modelName, deletedQss, -1
                 requestsChanged = true
 
         delete @_qsByRequester[computation._id]

            delete @_requestersByQs[deletedQss][computation._id]
            if _.isEmpty @_requestersByQs[deletedQss]
                delete @_requestersByQs[deletedQss]
                requestsChanged = true

        if requestsChanged and not @_requestsChanged

        for addedQss in qsStringsDiff.added
            if addedQss not of @_requestersByQs
                @_requestersByQs[addedQss] = {}
                @_incChanges @parseQs(addedQss).modelName, addedQss, 1
                requestsChanged = true
            @_requestersByQs[addedQss][computation._id] = computation

