When using the SUM function, most people set up totals at the bottom of spreadsheets:
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This is fine when there are a fixed number of rows, such as 12 months in a year.
However, when dealing with varying number of values, such as expenses, the layout has problems:
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To add a new expense, I need to insert a row, add my new expenses, and then check if my SUM formula covers the new data.
It’s much easier to set out such a spreadsheet with the totals at the top:
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Now, I can just keep adding expenses and the formula in cell C2 will keep on recalculating. Just make sure that you use a large enough area (700 rows should be fine!) and you don’t put anything else underneath the expense list.
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