Now that you understand the process I will explain how this shows up on your spreadsheet report that you got from the last blog.
Days interest is calculated so this should be the number of days in the month. Because is interest is calculated daily and charged monthly, you have to know the number of days.
The Opening balance came from what you said was your mortgage's outstanding balance.
The Monthly Income is the total of your payments from e.g. wages, government benefits, lotto wins, etc. etc.
( I put this at the first of the month but in reality, receipts happen over the month
and can be quite random. This makes some difference to the total numbers but I
did tell you that everything was approximate. Plus I am not a fancy programmer so
this was the best I could do.)
Interest is the total interest on the outstanding amount of the mortgage calculated daily charged monthly.
Monthly expenses are whatever you said you needed to live on exclusive of mortgage payments.
Closing Balance is the mortgage outstanding at the end of the month.
Look at the movements on your report.