You can use group assets in order to meet the requirements for depreciation at the asset class level according to ADR regulations. Create a group asset (sub-number) for the respective vintage year, and assign all the appropriate assets to this group asset. (Refer to Group Assets). You also need to make the following settings in Customizing:

• Specify the depreciation areas in which you want to manage group assets. The indicator for this is found in FI-AA Customizing under Valuation ® Group Assets.
• If you choose to manage group assets as separate asset classes (with their own account allocation), you need to create these asset classes. Set the indicator in these asset classes that specifies they can only be used for group assets.
• Specify the accounting method to be used for asset retirements. You make this specification in the Customizing definition of the transaction types for asset retirements (Transactions ® Retirements ® Define transaction types for retirement). Also see Posting Gain/Loss.