How can I add a second shipping table rate. I'm using the table rate as my shipping which is working great but, I want to add another table rate, so I can have two shipping selections based on the table rate.

For example.
Regular Shipping Price and Express Shipping Price. Right now I only have my regular shipping price set since i don't see how I can add another table rate for my express shipping prices.

I'm using the newest version of zen-cart.

Thanks for any help in advanced,

Chad