Calculating annual (& YTD) account credits from a dated record of monthly credits

Hi QP....Thank you very much for taking time to reply. The method looks really interesting. However, I realise and must apologise that I have not explained the problem clearly enough. To clarify, for example for AC01; The account was opened on 010216 with a payment of £650 per month. Payments of £650 per month were made on the first of each successive month until 010621 when the monthly payment was increased to £660 per month. This new monthly payment of £660 continued every month thereafter. The intention is increase the monthly payment to £700 on 010224. This would mean that the annual totals for each of the years from 2016-2022 would be the sum of all the monthly credits in each of those years; eg for 2016 the sum would be 11 x £650 = £7150. For the current year, the annual total would depend on the current date and for dates in the future the total would be displayed as zero until that date had occurred. The same applies to all the other accounts. I hope that is clearer. Many thanks Fraser