Hi @bobcat - I like your idea and now I’m contemplating something similar for a car loan. As of now, I update the monthly balance each month manually and paste it into the Balance History manually. But it would be nice to achieve your suggestion of a no touch solution since the balance is known ahead of time.
Your question got me to thinking… Apps Script is a good idea and also came to my mind as I’ve been considering it as a method to more quickly load my numerous manual account balance updates on a monthly basis.
But I’ll throw another idea out there as a more low-tech solution. Since you will eventually have line item entries in the Balance History for each payment milestone on the loan, you could just pre-load them all at once at the bottom of the sheet, and make them “activate” only when they come due. Similar to how you’re using TODAY(), you would compare the date of each payment with today and then turn the data on when it’s time. Below is a screenshot of the idea where you can see payments in 2023-2024 are active and the rest are sitting waiting (empty of data, but with formulas underneath):
I think my Balance History sheet is an older version so you may have different column headings, but the idea is that the date and most of the data only becomes visible when it’s time. When a sheet Fill runs via Tiller, a sort is going to occur and the relevant “active” lines are going to take their place in the main data field and the others will hang out at the bottom. I did test it on a live sheet and the Tiller fill will delete the line if you don’t have some data somewhere in it (even with formulas present), so that’s why I have a zero balance for the inactive ones.
I haven’t included all of the formulas here unless you want to see more, then I can share an example sheet. But for the Date column it looks something like this:
=LET(pmt, XLOOKUP(O9818,AmortSch!$G$2:$G,AmortSch!$E$2:$E), IF(pmt<=TODAY(),XLOOKUP(O9818,AmortSch!$G$2:$G,AmortSch!$E$2:$E),IFERROR(1/0)))
I’m looking up the date and balance columns in the Amortization schedule where I’ve placed the same identifier as shown in the last column of the screenshot. I believe that a solution could be made without this XLOOKUP by encoding the dates and balance formula within the Balance History formulas, but the extra column does give an added benefit of quickly locating those rows.
I haven’t tested this extensively but I expect to try it out with my loan. I’ll report back if I find any issues.