Configuring a depreciation key with different formulas per year and after technical improvement

[Edoardo21]

Subject: Need help configuring a custom depreciation key with different formulas per year and after technical improvement by standard SAP.

Hi SAP Community,

I need to configure a rather specific depreciation key for a customer, and I’d like to ask for your advice.

The requested logic is as follows:

• Depreciation amount in the first year:
  Depreciation amount in the first year = Acquisition value / Depreciation coefficient for the first year,

• Depreciation amount in the following years:
  Depreciation amount in the next years = (2 * Net book value) / (Depreciation coefficient for next years - Already depreciated periods)

• Depreciation amount after a technical improvement:
  Depreciation amount after technical improvement= (2 * Net book value) / (Depreciation coefficient after technical improvement - Already depreciated periods after certain technical improvement)

So basically, we have three different formulas:

1. One for the first year,

2. Another one from the second year onward,

3. And a third one that should apply starting from the moment a technical improvement (capitalization) occurs.

Do you have any idea how this could be configured in SAP?
Is it possible to handle all three cases within a single depreciation key, or would it require multiple keys or a BAdI implementation?