Reason: When a visitor sticks around on your site for a minute or less, you can consider their stay to be negligible. When a visit exceeds that amount of time, the visitor has more potential for becoming a client and an increased chance of converting on your calls-to-action. If a visitor spends a considerable amount of time on your website, they are likely to come back or to take action on conversion areas you have included in your site (call-to-actions, downloads, contact forms, etc.).
Now the ad servers don’t create this table themselves, they license it from another company like MaxMind or DigitalEnvoy, whose primary business is geolocation data. This is no enviable task; IP addresses themselves don’t necessarily have an obvious pattern in the way they are assigned like a telephone area code would. It’s a bit like solving a mystery, and the geolocation companies use a variety of methods to approach the problem. /injects>