Rules of operation

To top down spread, you need a writable data source with Excel Type 1 and Type 2 formulas or a read-only data source with Excel Type 2 formulas and periodic data (not year-to-date data).
Top down spreading can be performed against all hierarchical dimensions (Period, Schedule, Unit, and custom dimensions). To top down spread, you must specify a value on a schedule line, not a schedule.
A value specified over an Excel Type 1 or MPCPushData formula is immediately spread to the formula leaf levels unless a cell is locked or the value exceeds a constraint (see also "Locking/Unlocking Cells" and "Setting/Removing Constraints")
If there is existing data in the levels below, the existing data will be used as the spread weights.
If there is no data in the levels below, the data is spread evenly.
If you type over a formula with division (for example, X=Y/Z) and both Y and Z are unlocked, then Z is treated as locked, by default.