Actual receive dispersion. Data for this variable is only available from the subtending card. This data is retrieved from the SP with GET-NEXT. When there is no real-hardware the GET request will get no data and GET-NEXT will return SP data (most likely UNKNOWN). When there is hardware, the GET-NEXT will still return SP data but the GET will get the actual reading from the hardware. This approach is necessary to make sure table views and index discoveries are not stalled on queries to the subtending cards.