Hi Zen Hui,
As per your requirement it is understood that for an Asset you need two different Depreciation rates/ lifes.
to achieve this You can manage two depreciation Areas one is with ordinary depreciation and another one is with special depreciation. we have depreciation base method it differentiate ordinary depreciation and special depreciation , interest.. in SAP depreciation types: ordinary, special and interest amount can be calculated automatically with the depreciation key and unplanned depreciation we need to calculate manually.
For one depreciation area you can assign dep key having ordinary depreciation as base method
For other depreciation area(tax) ( special depreciation) you can assign dep key having special depreciation as base method.
You can have another depreciation area - i.e derived depreciation area which is the difference between ordinary and tax depreciation and this difference you can post to the deffered reserve account to deduct from the Net book value of the ordinary dep area i.e corporate accounts book area.
Thanks and regards,
Surendra..
