Does a Party wall count for the Window to wall ratio?

Hi there, Im modelling a corner building, which has two adjacent buildings so only the façades facing the street are in contact with the exterior environment. I'm planing to model the site, both for the proposed and baseline model, and a single orientation for the baseline. I was wondering if party walls (division walls shared with adjacent buildings) would count for window to wall ratio. This is a big difference, since the builidng has 70% glassing area in the two façades facing the street, and 0% in party walls, as you would imagine. So taking into account party walls would end up in a global 35% WTWR instead of 70%. Thanks. Best regards, Santiago.