Facebook has seen a tripling in the use of its automated online-advertising system in the last year, Bloomberg reports. The growth is due in large part to the small- and medium-sized businesses that are starting to embrace the social-networking site.

The service lets companies target users based on information in their profiles, Tim Kendall, Facebook's director of product marketing for monetization, told Bloomberg.

"You basically just have a greater diversity of people using our ad system -- lots of businesses, lots of local businesses finding success," Kendall added. "It's really been a steady, successful growth pattern."

Facebook declined to reveal how much revenue it is making on the service, which was first unveiled in 2007, but COO Sheryl Sandberg recently said the company's overall revenue may climb 70 percent this year.