Write some software for web database

Modify our existing online database with more intuitive dashboard, confirm calculations are accurately programmed, add in fields and calculations as indicated on documents provided. verify/confirm that calculations are being done according to the following logic. When we refer to "Looking forward re record activity 3 months, 6 months, 9 months etc." that means that we need to be looking forward 3, 6 and/or 9 months from the date that the customer records was added to the list. Here's where we are concerned we are being misunderstood. We are concerned that we are calculating data based upon "Records Added to List Between Simple Dates). While we LOVE the date range for the reports that you added, and we wish to keep this, we want to make certain that the calculated data points are taking the day they are added to the database and looking forward INDIVIDUALLY FOR EACH RECORD, calculating any order activity and adding that together with the other 3 Month, 6 Month, 9 Month totals and reporting accordingly. Example... Prospect A is added 2/1/2016. That prospect would obviously show on a report run for the 1st quarter of 2016. However, that Prospects 3 month data would include any activity that he had from 2/1/2016 through 4/30/2016 and said activity would need to be SUMMED together and AVERAGED out with the other records added and their subsequent values. Thus, a person included in a report covering records added for 1st quarter, if he were added on 3/31/2016... his 3 month data would be any data/activity recorded from that time through 6/30/2016. I hope I am not making this confusing. But this is of paramount importance to the entire logic and purpose of the software.