The number is in the CloudFlare blog post that started this. > Based on data across the CloudFlare network, 94% of requests that we see across the Tor network

The number is in the CloudFlare blog post that started this. > Based on data across the CloudFlare network, 94% of requests that we see across the Tor network are per se malicious. That doesn’t mean they are visiting controversial content, but instead that they are automated requests designed to harm our customers.