Question: Parallel Ledgers in AA transfer to CO

Hi Experts,

Scenario:

We plan to implement parallel ledger.

0L for US GAAP,   Z1 for local GAAP

In Asset Accounting, we create following depreciation ara,

01 ---- US depreciation  assigned to ledger 0L

30 ---   Local depreciation assigned to ledger Z1

50 ---  difference 01-30, assigned to ledger Z1.

It is OK to fulfill finance requirement for US GAAP and Local GAAP.

According to SAP help, only depreciation area 01 is transfer to CO.

So that means only the US GAAP value is shown in CO. That means Local GAAP depreciation will not show in CO.

My Question:

1.  If product costing calculation have to use Local GAAP depreciation, How to realize it?

2.  Why can we transfer all depreciation area's data to CO?

3.  What is the priciple for designing the relation of depreciation ad ledger?

thanks