One million.
That's how many new Americans signed up for Twitter in the past three months, a number that failed to inspire investor confidence in a social network with a nagging history of growth issues.
See also: The Year in Twitter: Top Milestones of 2013
Twitter announced the number on Wednesday at its first earnings call since going public. There's no denying this growth is small, and its stagnant U.S. user base was coupled with relatively weak international growth — just 8 million new users in the same time period.
Twitter Reach: Q4’13 avg Monthly Active Users 241 million, up 30% y/y. #TWTRearnings pic.twitter.com/74Eva0gRqc
— TwitterIR (@TwitterIR) February 5, 2014
The majority of Twitter's advertisers come from the United States, and now the consumer base they are trying to reach has flatlined. U.S. advertisers generated 73% of the company's ad revenue in Q4. For the past two years, Twitter's U.S. users have represented just under 25% of the company's total user base. It's now at just 22% — the smallest it's ever been.
Arvind Bhatia, an analyst with brokerage firm Sterne Agee, changed Twitter's stock rating from "neutral" to "underperform" following the call. "Most people came out scratching their heads saying, 'If at this early stage they're not getting the eyeballs, what are advertisers going to say when they see there's no growth?" he told Mashable's Seth Fiegerman on Thursday.
This viewpoint was apparently shared by others on Wall Street, as investors responded harshly to the news: $TWTR was down nearly 25% at market close on Thursday.
Growth will continue to be a point of focus for the company moving forward, but not everyone is worried. Marketers, for one, seem to be preaching patience.
"I think it would be a mistake for advertisers, Wall Street, humankind to look at one quarter and say 'Oh my God, this is not what we thought it was,'" said Jesse Pujji, CEO of Ampush, a software company that helps clients advertise on Facebook and Twitter. "That happened with Facebook and a lot of people lost a lot of money, and a lot of people made a lot of money and realized that it was just the beginning and really early."

Twitter's 2013 revenue was more than double the company's 2012 revenue total, a definite bright spot during earnings.
Image: Twitter
Even if Twitter growth has slowed in the U.S., 54 million users provide a much larger reach than most advertising opportunities, Pujji said. Twitter offers targeted ad opportunities that are still better than most alternatives.
Aaron Goldman, chief marketing officer of Twitter ad partner Kenshoo Social, also compared Twitter's ad strategy to the early days of Facebook ads. Facebook turned things around once advertisers familiarized themselves with how ads work on the platform, he said, and the same will happen with Twitter.
Twitter's ad revenue was the bright spot from the company's earnings call, easily beating Wall Street estimates. Goldman said he believes the company has only hit the "tip of the iceberg" in terms of advertising potential. He expects it will be another year or two before Twitter and its ad partners fully grasp the opportunity.
"I can't speak to how much patience investors will have, but I think over the next 12 months, we're going to see much more maturity of the Twitter ad platform," he said. "In that same time frame, 12 to 24 months, Twitter will become a must-buy for advertisers on the same level as Google or Facebook."
Sounds like good company — if investors are willing to wait.
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