The company’s user base grew by less than 1% worldwide, to 319 million monthly users, and in the U.S. it didn’t grow at all. Chief operating officer Anthony Noto said Trump’s use of Twitter “has broadened the knowledge of the platform and how it can be used,” but that this has not translated into actual signups.

But flat growth in users is just part of the problem for Twitter, or rather, just one in a series of interconnected problems. The company’s revenue grew by just 1% in the fourth quarter, and advertising revenue—which makes up the bulk of Twitter’s business—actually fell compared with the same quarter a year earlier.

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Some of the weakness in revenue was expected because Twitter has been restructuring its advertising operations over the past few months. (Its head of sales left the company in November, one of a number of high-level departures.)

Despite these justifications, however, seeing ad revenue shrink in what is typically the biggest quarter of the year for advertising was clearly not what investors were hoping for. Twitter’s shares (TWTR) dropped by more than 10% on Thursday after its results were released, erasing all of the gains the stock saw over the past few weeks.

Twitter’s guidance for the current quarter was also much more pessimistic than analysts and investors had been expecting. The company now says it hopes to have adjusted earnings of about $85 million, which would be less than half what it made in the same quarter last year.

Twitter's revenue growth falls to 1%, slowest in the company's history. $TWTR pic.twitter.com/oiyyo90IgV

— Charlie Bilello (@charliebilello) February 9, 2017

In his opening remarks on the company’s earnings conference call, Twitter CEO Jack Dorsey tried to strike a positive tone, saying the company had been through a “transformative” year in 2016, and that it was seeing strong growth in usage.

According to the company, daily active usage of the service rose by 11% in the most recent quarter, compared to the same quarter the previous year. But Twitter didn’t provide any actual numbers for its total daily active user base, and the growth in the number of monthly active users was dramatically smaller than that.

The challenge for Twitter is that while it is trying to reinvent its user experience in order to get more sign-ups—or to turn occasional users into dedicated users—it is also having to reinvent its ad business at the same time because it is clearly not working.

Dorsey said that the company is taking the same approach it took to the user side, namely to “reset and focus on our strengths [by] clearly differentiating and complementing Twitter’s real-time nature,” in order to show advertisers that Twitter works. But are investors going to wait around while Twitter tries to restructure that business?

In effect, Twitter has admitted that its current ad products—including “promoted tweets,” which were the cornerstone of its offerings until recently—are not working the way the company had hoped, and it is trying to come up with new ones. But it isn’t doing so in a vacuum, nor does it have the luxury of time.

Facebook’s ad business continues to grow dramatically, and the larger social network added almost as many new users last year as Twitter has in total. And then there’s Snap Inc., which is going public soon and is promising significant advertising revenue growth based around its video-centric messaging service. (Whether it can deliver on those promises is another question.)

https://twitter.com/MikeIsaac/status/829670450879827968

A few months ago, Twitter’s stock jumped dramatically after there were rumors that a number of potential acquirers—including Google, Disney, and Salesforce.com—were looking at possibly buying the company. But those rumors quickly evaporated, and the stock fell back to earth.

Dorsey argued in his remarks on the conference call that while the company “may not be currently meeting everyone’s growth expectations,” the influence and impact of Twitter as a real-time news source continues to grow. Unfortunately, investors may be running of patience waiting for the company to figure out how to turn its influence into cold, hard cash.