NEW YORK (AP) -- Twitter's stock is sinking on worries that the short online messaging service is not popular enough.
Twitter Inc. had reported stronger-than-expected revenue and adjusted earnings in its fourth-quarter financial report Wednesday, its first as a publicly traded company.
But its user numbers signaled that growth is slowing. Twitter had 241 million users at the end of 2013. The company added just 9 million new monthly users in the fourth quarter, only 1 million of which came from the U.S. It was adding an average of 16 million new accounts in each of the first three quarters of the year.
San Francisco-based Twitter's stock soared following its November initial public offering, causing many analysts to call it too expensive. It is down 21 percent at $52.20 in Thursday morning trading.