One Query with different focus

Hello alltogether,

I've got one issue and would be happy if someone can answer the following question.

I already developed one query which provides inventory reports.

I need for every month, the last inventory value, means month-end-values. This is not the problem, especially it can be solved by using customer exits.

The problem is: Additionally I need as a comparison value the first value of the year (01.01).

The structure will be as follows: 01.01. 31.01 28.02. and so on...

How can I handle this issue?

Thanks a lot for your answers