wear and tear
is there any function module to calculate wear and tear for particular asset?
When you look in asset accountingunder tools (spro) you can see the available user exits (badi's)
You can use an own base methods in the depreciation key. When this base method is in the depreciation key it is going to the user exit. There you can calculate what you want. To realise this is not a 10 minuts job!!
You can create to a depreciation area where you post this values on.