You'll need to include more than a basic level of development and calculation in your spreadsheet. There are lots of free spreadsheets on the web. Most of which are very simple and easy to build. People aren't going to buy a spreadsheet that they can get for free. Take yours to the next level by adding all the value you can imagine. Then research on how you can offer a little bit more on the development and functionality side.
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.
Spreadsheet applications are useful for home and small businesses. Some people keep a home inventory list on a spreadsheet and others use spreadsheets for a variety of applications. Creating your budget and maintaining it is easy when you use budgeting spreadsheets. These are also easy to print out if you desire.
The mentioned package includes valuable programmed spreadsheets such as the "Income and Residual Tracker" - provides professionals in the entertainment branch with detailed information regular and residual income; "The Biorhythm Plotter" - helps users in planning various events and actions based on Primary and Secondary Biorhythms (the spreadsheet solution allows users to choose the right timing for their actions according to personal intellectual, psychological and physiological factors); "Basic Actor Package" - designed to facilitate the process of calculating expenses.
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