Hi,
You might want to try SIS - Sales Information System for this. Good old SIS which is now a days not being used by very few people.
I think it has been a while for me on this topic, but I feel there might be some way to track this info without having to create the Z Table that you are thinking of. The Custom Table might be complicated with all the stuff you are thinking of.
I am not saying that SIS will give you the full information the way you are looking for but you will reach half way there. There are two major components for any IS[Information Structure].
- Standard Analysis
- Flexible Analysis
You have to create / use Info Structures which have characteristics and key figures, assign updates rules, etc. to have this work. These are basic stuff. The Updates to these figures can be :
- Synchronous
- Asynchronous
You could probably use this information to manipulate the prices as you want.
Do note that this will be a major activation of a standard feature, so would need a buy in from others. If it is already a Live System you should be aware of what impacts it has standard SAP Reports.
Coming back to your original idea, assuming that you are successful in using the Z Table route, you still need to have logic in pricing to be able to compare the different volumes during some time period and do what it has to do in actual pricing during the Order and Billing Transactions.
This is going to be the case for both scenarios - your Z Table or Standard SIS.
Thanks.