One issue that crops up surprisingly often in spreadsheets is repeating the same calculation. I see two key problems with this:
- Inefficiency.
- Harder to maintain.
Inefficiency
Imagine you didn’t have a spreadsheet.You would never work out the same thing twice, especially if it wasn’t easy! You’d simply find where you had done it before and use it again.
You can do the same thing with spreadsheets. Just store the result in a cell (preferably an appropriately named one) and you can reuse it.
Maintenance
If you duplicate a calculation then you have to maintain every copy of it. Say something changes – perhaps a new parameter is added. Then you might change the calculation in one place but not the other. Or you might make a mistake in one of them. Removing duplication frequently makes it much easier to find and fix errors.
Like so many things it boils down to common sense. Have you experienced spreadsheets like these? Any other top tips? Let me know!
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