SCALE with formatted output

In the OpenHAB Documentation about SCALE Transformation Service I can read about the capabillity to format the output of Scale:

At last, Scale transform can take care of formatting an output with this entry :

format=%label% (%value%) !

Where :

  • %label% will be replaced by transformed value and
  • %value% is the numeric value presented

but nowhere I can find how to implement this feature an no examples.

Can someone give me an example (code) how to use this feature?