Many spreadsheet applications nowadays have functionality above and beyond the traditional, offering a variety of charts, look-up tables, databases and more functionality than can be mentioned here.
When VisiCalc hit the scene back in the eighties (in the last century), the relatively small group of Apple II users went crazy. It was like manna from heaven for the poor accountants, scientists and engineers who were used to filling in enormous analysis sheets with a pencil. Now, they could use VisiCalc to do the same task, AND calculate the result automatically.
You may also want to track your current spending on one sheet with columns for different categories. Some individuals will list the budgeted amount in one column and then list the actual amount spent in the column next to it.
These are the pros and cons of selling spreadsheets. The real beauty in this idea is that you could do the work once and there is no limit to how much you can earn, especially with effective use of the internet and other mass communication tools.
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