Adjusting prices globally

My freind who I am setting this cart up for sells platinum rings. Below is an email he sent me which describes what he wants done. Basically I was wondering if there is a way to enter a number in the admin section of the cart that will globally change all 100 products prices across the board at once. See below:

We get the daily price per troy ounce of Platinum from www.thebulliondesk.com (up in the right hand corner of the page), we then use that amount and divide it by 20 to get price per pennywieght. The price per pennywieght is the number that we need to plug into the store setting when the price per ounce changes. We need to be able to plug that number into store settings and have it feed through to each ring style to adjust the prices accordingly.

May the admin please respond to this thread and tell me if this is possible?

I don't want to add 100 products unless we can get things to function properly.

Thanks for everyones help along the way.

You'll need to have custom code written to auto-update all prices.

You could do it either based on product weight and build the price as a factor of weight and cost per pennyweight, or you could do a global price update daily when you obtain the updated pennyweight amounts, probably via an admin interface where you would enter the new price and tell it to go and edit the price on all products.

I suggest posting in the Commercial Help-Wanted area if you are not comfortable writing this code yourself.

Thanks for your answer. I will post over there now. Have a nice day.