Item definition for Homegear / Homematic Duty-Cycle

Hello, i need an example of the definition of the Duty-Cycle CHannel of a Homegear-Bridge.
What I have so far:

Things:

Bridge homematic:bridge:masterpi [ gatewayAddress="127.0.0.1" ]

items:

Number  Homegear_EG_Duty            "Erdgeschoss Duty Cycle [%d %%]"  <qualityofservice>    (Homegear)  { channel="homematic:bridge:masterpi:DUTY_CYCLE_RATIO"}

But this channel syntax is obviously wrong. What has to go there???
Thanks in advance,
Ingo