Alexa's certified program and pro metrics.
http://www.alexa.com/siteowners/certify
Analytics and Tracking · Audience Measurement · Visitor Count Tracking
Get access to data on 296,711 websites Alexa Certified Site Metrics Customers. We know of 25,066 live websites using Alexa Certified Site Metrics and an additional 271,645 sites that used Alexa Certified Site Metrics historically and 9,485 websites in the United States.
Get a list of 296,711 websites using Alexa Certified Site Metrics which includes location information, hosting data, contact details, 25,066 currently live websites and an additional 56,212 domains that redirect to sites in this list. 271,645 sites that used this technology previouslyand 9,485 websites in the United States currently using Alexa Certified Site Metrics.
Countries
Financial
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Region
These are sites that we think might use Alexa Certified Site Metrics in the future because of their similarity to other sites that already do.