Discounts structure in pricebooks

Discounts structure in pricebooks

I am using Zoho to generate quotations. I have about 200 products that I am importing into Zoho, which works well. Now the problem comes when I try and create pricebooks for my 3 levels of client (Silver, Gold, Platinum).

Presently to do this, it seems like I have to manually enter the discounted price for each and every line item in each pricebook. This means that I have to manually type in 600 line item prices (3 pricebooks X 200 products).

Is there no way one can associate a discount from the unit price for each pricebook, so that all the line items are discounted by the selected amount. So, for example, Silver (10%), Gold(20%) and Platinum (30%)