CIMM DEFINITION:  A metric which compares usage to the potential iTV customer universe either within a MVPD footprint or a DMA; based upon iTV HH data comparable to a rating Calculated by dividing the total iTV HH by the number of HH that interacted with the session. Could be by spot, by flight, by day, week, month. (Source: CTAM Advanced Cable Solutions Consortium, itv Metrics)