docs: def _update_data_dict(self, data_dict, back_or_front):
          """
          Adds spct if relevant, adds service
          """
          data_dict['back_or_front'] = back_or_front
          # The percentage of used sessions based on 'scur' and 'slim'
          if 'slim' in data_dict and 'scur' in data_dict:
              try:
                  data_dict['spct'] = (data_dict['scur'] / data_dict['slim']) * 100
              except (TypeError, ZeroDivisionError):
                  pass