Ad company databases map 95% of IP addresses to individuals. You can buy the names, addresses, phone numbers, and email addresses of your website's visitors.
I have a dynamic IP and I was curious about how often it changed (I wanted to host some minor stuff out of my house).
So I rolled my own DDNS solution, and have it send me a text every time my IP changes. I have only seen one change in the last six months, and that was when the neighbourhood’s power was cut for two hours for maintenance. Rebooting or temporarily powering off my router doesn’t seem to be enough to force a change on it’s own, I believe it’s only when larger equipment upstream from me powercycles that my IP changes.
So (at least in my experience) the “dynamic-ness” of my home IP is relatively small.
Ad company databases map 95% of IP addresses to individuals. You can buy the names, addresses, phone numbers, and email addresses of your website's visitors.