Google has revealed some statistics around the steps it took in 2013 to remove bad ads and advertisers from systems.

In a blog post, titled ‘Busting Bad Advertising Practices — 2013 Year in Review’, Google stated that it removed more than 350 million bad ads from its systems throughout the course of the year, a significant increase from the 220 million it removed in 2012.

The number of advertisers it disabled dropped from over 850,000 in 2012 to more than 270,000 in 2013.

“We attribute this decline to scammers — counterfeiters, for example — being thwarted by our safety screens and searching for less-secure targets,” the company said.

By the end of 2013, Google claims it had also blacklisted more than 200,000 total publisher pages, an “encouraging” decline from last year, and disapproved more than 3,000,000 attempts to join its AdSense network.

It also removed more than 250,000 publisher accounts for various policy violations, including more than 5,000 account removals for violating copyright policies.

Google continued: “This is an ever-evolving and ongoing fight. Bad actors are relentless, often very sophisticated and will not rest on their laurels. But neither will we. Nothing is more important than the security of our users and we’ll continue to work tirelessly to keep them safe online.”

Check out some more Google stats from 2013 in the infographic below. .