Twitter users sending 200 million tweets a day

Twitter users are sending 200 million tweets a day, up from 65 million a year ago, the micro-blogging service said Thursday.

"For context on the speed of Twitter's growth, in January of 2009, users sent two million tweets a day," Twitter said in a blog post.

The San Francisco-based Twitter was founded in 2006. It has more than 200 million users.

According to a recent study by the Pew Research Center, 13 percent of the online US adults aged 18 and older use Twitter, up from eight percent in November 2010.