Help with automatic dates

[foxx60]

Hello:

I have craeted a spreadsheet with names and dates which have due dates for each name.
My spreadsheet has the names in the first column; the type of follow up eg. 30 days, 60 days etc. and the last column has the date that the individual follow ups are due. How do I program Excel so that the due dates for each customer is automatically updated every 30 days, 60 days etc. Also, how do I link the cells with the dates to the individual columns. I hope that someone can help.

Thanks.

[hideki]

How do you calculate the due date? Do you have cell that contains the 'from when' date?