Less than a quarter of Twitter's 75 million registered users are active on the microblogging site, while 17 percent have no followers.

The report, compiled by Barracuda Networks Inc., an e-mail and Web security company, found that only 21 percent of people who have accounts on Twitter, actually use their accounts regularly.

Moreover, today there are 34% of users who have not tweeted since they created an account, said Paul Judge, chief research officer at Barracuda Networks, in the report.

While that still seems like a fairly high percentage of inactive accounts, he noted that the percentage of inactive users is down from from 37 percent in June 2009, demonstrating that people are becoming more active.

The study also found that 17 percent of Twitter users have no followers at all, a significant improvement over the 30 percent who had no followers in June of 2009.

Meanwhile, 61 percent of Twitter users today have less than five followers, compared to 70 percent last June.

The report said that Twitter's growth rate spiked at 21.17 percent in April 2009, during what Barracuda calls Twitter Red Carpet Era -- November 2008 to April 2009 when several celebrities joined Twitter.

It was during that six-month period, the report found that 27 of today's 50 most-followed Twitterers, and 48 of the top 100, first opened up an account with Twitter.

With the increased visibility of Twitter, the millions of fans of many of these celebrities also joined Twitter, causing the Twitter growth rate to spike -- from 2.02% in November 2008 to 21.17% in April 2009, the report said.

Forty-nine percent of Twitter accounts were created during the Twitter Red Carpet Era.

Software Twitter