Forecast - Line Chart - Month does not work as expected.

Hi,

I'm using the forecast feature in a line chart. The problem is that when I want to do month forecast, make a forecast to months number 13 to 20 (which does not exist).

It only works with Date, because with Year, the forecast is always the same. I've tried to create a Date Hierarchy but still does not work.

Anyone has a clue?