How to generate account statements with running balance

[BlueTech]

Hello,

I'm relatively new to AppSheet and currently working on a project to generate comprehensive statements for each customer that detail all transactions, payments, and include a running balance. There's a cell in the AppSheet with a specified date from when to display the transactions, and this can be changed by the user at any point. Transactions that occurred before this date are consolidated into a balance, and displayed on the first row of the statement as "Balance Brought Forward", and then the rest of the transactions (from after the specified date) are displayed.

While I've successfully implemented a Google Apps Script to create and email invoices as per my requirements, the process is quite time-consuming, averaging 30 seconds per statement. I assume having an AppSheet bot generate the statements would be less time consuming than relying on external scripts.

From what I've read so far, it looks like that the best way to get the running balance to show on AppSheet generated files is to have a virtual column with the running balance on the relevant tables. As of now, my tables don't have a running balance (the apps script adds the running balance dynamically to the statement). My concern is that having a virtual column to get the running balance on every row would potentially impact the app performance, especially given the volume of data involved (approximately 40,000 transaction records).

I would greatly appreciate insights or advice from anyone with experience in handling similar scenarios within AppSheet. How can I replicate the desired statement format effectively within the platform?

Thank you for your assistance.