google traffic estimator-region vs radius?

[ronr]

Can someone explain this to me?

I used google traffic estimator to estimate traffic for several key words. The region was a large region that encompassed 3-4 major cities

The estimate for this large region was only 5-6 clicks per day.

Then I tried a radius of 15 miles in that same region (which only covered a portion of the larger region) and got estimates for the same key words at 155-184 per day!

All the other settings were the same.

Large region estimate of 5-6 per day
15 mile radius in that same region 155-184 per day

Can anyone explain this to me?

Thanks, Ron