More than 175 million people have registered for Twitter accounts. Which sounds very impressive. Sadly for the microblogging startup's multi billion dollar valuation, at least 68 percent of those registrations are considered dormant.

There are only 21 million Twitter accounts that come close to Twitter's definition of "active user," i.e. they follow 32 or more other people on the service, a tipster with access to privileged Twitter data told Business Insider. There are 56 million "active" accounts if you use a more generous definition, people who follow at least eight other accounts. Either number is well under a third of Twitter's more than 175 million registered users.

Twitter, in other words, is tough on newcomers. To make them feel more at home, consider doing more Justin Bieber retweets, getting into meaningless tweet-fights, and inventing more cryptic #hashtags. Get to it, Twitter old timers!