This is how we determine the potential visitors to your site.
The Estimated Traffic metric is based on the monthly search volume and per-SERP clickthrough rates.
This number is summed across all the results that appear in the same SERP for each domain.
Essentially, the formula is:
Estimated Traffic = (Search Volume) x (CTR).
If either of those values are 0, Nozzle will report the Estimated Traffic as 0.