Referal stats?

[jfremont]

I am a numbers kinda guy, I love to know the stats. For example advertisers that mass mail coupons are extremely satisfied if they mail out 10,000 coupons and they recieve about 100 - 200 responses. they are working with a 1 to 2 percent success rate.

what I am curious is if anyone knows that stats on how their referral building program is working, and what they are doing to make it work for them. and what percentage should I be happy with for gaining referals.

Thanks