Help : how to create a sliding scale from a few data only?

Hello! I am working on the new website of my company and I have tons of data to create (prices). This is how it works : the company is a printing company. Today our prices online are for example : $30 for 200 units, $50 for 500 units, $80 for 1000 units and $5 for 100 units more until 5000 units. As you notice, prices are on a sliding scale the more you go up (per unit). You clic on 200 and pay $30. However, we want to allow our clients to order 100 units per 100 units. So : 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 and +100. Is it possible for Excel to calculate the missing quantities from these quantities (or from a price per unit)? Which would give : $15 for 100, $30 for 200, $36,66 for 300, $43,23 for 400, $50 for 500, $56 for 600 units and so on? I sometimes have spreadsheets per 25 units up to 5000 to calculate on 10 different papers and 6 different formats + one or two-sided and it requires a very long time when it is manually done (knowing that we have dozens of different printing media!!!). Do I need to insert the blank columns or can Excel create everything automatically? I really hope someone can help me with that tricky question because I studied a semester Excel at college but it was a long time ago....! if so, we will be happy to print for free 200 business cards on a thick or textured paper if you have your PDF files ready ;-) I am working on Open Office but also have Excel 2008 for Mac. Thanks a lot everyone! :-) Regards, Clement.

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