SAP Hana License Measurement (XML File)

Hallo,

question to the experts:

we I make a license measurement for SAP Hana (creating the XML) there are different results in the XML's when I do the measurement for example every month.

What is the meaning of: GenericID and Unit in the XML. 

-<Result>

     <GenericID>...................</GenericID>

     <Unit>..........................</Unit>

<Counter>5</Counter>

<PerStart>20150601</PerStart>

<PerEnd>20150630</PerEnd>

</Result>

For the same SAP system I have differnet ID's (mentioned above) in each xml.

Is there a note or document, which explanes the content and metric of the SAP Hane license measuremnt XML file ?