Clouds item with Weather binding and Yahoo

Just set up the weather binding with Yahoo and temp/humidity/pressure etc. is working perfectly.
However, I don’t get a value for the

Number   Clouds   "Clouds [%.0f %%]"   {weather="locationId=home, type=clouds, property=percent"}

Is it just something I’m doing wrong or is this something that Yahoo doesn’t supply.

Any suggestion as to which other provider I should use instead of Yahoo (live in Germany)?