I have a Forecast Series which has no proportional series defined in Data Properties? How this serie

I have a series Final Forecast. This series has no proportional series defined in its data properties. The series has both client and server expression. In a Worksheet, I zeroed out all the values of this series for an item for all customers under a particular org at the lowest level. Now i am giving input in this series for this item at a higher level, i.e. only the item and the Org selected as aggregation level.

but the data is not splitting equally in the lowest level. Can any one help me how this series is dis-aggregated?