The major advantage of online advertising is the ability to target ads to consumers based on each individual’s interests, geographic location and other personal characteristics, which ultimately makes these ads more effective for marketers and consumers alike.

However, the fact that advertisers are able to track people based on their interests and online behavior is understandably off-putting to many Web users. As a result, consumers and consumer advocacy groups have come out to demand transparency with regards to advertiser practices.

Since this push, the Federal Trade Commission (FTC) has gotten involved, most notably by introducing the Final Privacy Framework Report to outline guidelines as to how companies can and cannot use consumer data gathered on the Internet.

Two primary aspects of the industry’s self-regulatory commissions, the Network Advertising Initiative (NAI) and the Digital Advertising Alliance (DAA), have both seen a significant swell of participation over the last few years. At present, the NAI boasts over 80 different companies as partners.

To opt out or not to opt out ...
The real important figures, which are outlined in a new infographic by Loeb & Loeb, have to do with how many consumers are actually opting out. In the last four years, nearly 10 million users have visited NAI’s opt-out site. That may not seem like much, but 2011 saw 5.9 million of those visitors, nearly twice as many as 2008 to 2010 combined. In that time, 1.75 million (or about 17 percent) of these visitors have opted out of cookie tracking.

In the end, this seems like it is going to be a real issue for online advertisers. One Pew survey points out that as many as 73 percent of consumers are “not OK” with search engines keeping tabs on their searches to personalize results, which is in effect the same process that marketers use to serve targeted ads. This begs the question: If the majority of Web users begin to reject behavioral tracking, how can (or should) marketers attempt to continue serving relevant ads that are as effective as their current offerings?

View the full infographic below: