Are there any DSL ISP's who renew static IP addresses often?

I checked my IP address and it has remained the same for months. I'm concerned since this unchanged IP address can be used as a supercookie by websites to track me. Are there any DSL providers who renew static IP addresses often so you don't have the same IP address for months? Isn't this a security issue since even though the DSL modem has a firewall, a hacker can still find a vulnerability in your modem and attack your system?