What is the average customer response percentage for business cards? How many cards for x amount of responses?

I am advertising a business and want to know how many cards versus my desired response rate. I have put out some cards and have gotten a few responses, I just want some averages, so I can determine my goals. My business here, www.my.ws/centerion or www.onlyoneexists.ws

Postal mail response rates are 1-3% , You need to do mailings in the 1000′s before any sort of viable response happens.
Good luck