Social media leader Facebook Inc. (FB) is comfortably ahead of rivals Twitter Inc. (TWTR) and Snap Inc. (SNAP) in terms of total revenues and users, but its growth rate is stalling, CNBC reports. Daniel Ives, chief strategy officer and head of technology research at market research firm GBH Insights, tells CNBC that Facebook used to be "the only game in town" for advertising on social media. Now, he says, up to 20% of Facebook's advertisers are experimenting with Twitter, and some also are giving Snapchat a closer look.

Over the past six months, through the close on February 22, shares of Twitter have surged by 93.1%, Snap is up 20.5%, and Facebook has gained only 5.5%. During the same period, the S&P 500 Index (SPX) is up 10.3%. 

It should be noted, however, that Facebook stock has had a great run since its 2012 IPO, up 326%. By contrast, Twitter and Snap have been losers since going public. Hurt by bad management and missed targets, shares of both are below their initial offering prices. 

'Attractive' Ratings

Per CNBC, Ives gives "attractive" ratings to both Twitter and Snap, with respective price targets of $38 and $25, or 18.3% and 42.8% above their closing prices on February 22.

Twitter recently reported the first profitable quarter in its history. Snap remains mired in losses, but its recent quarterly revenues were 13% above consensus estimates, and its per-share loss was 19% less than anticipated, per another CNBC report.

Ives still views Facebook as a "favorite name" in the social media arena that he rates "highly attractive," largely due to its massive monthly active user (MAU) base of more than 2.1 billion people around the globe. Its smaller rivals have users in the hundreds of millions, CNBC says. However, Facebook's growth is reversing in the U.S. and Canada, slowing in Europe, but still brisk in the rest of the world, per data presented by TechCrunch.

Not Going Viral

Facebook has revealed that users spent an average of 5% less time on the site during the fourth quarter of 2017, partly due to changes in its video recommendations, CNBC indicates. This change mainly affected viral videos, TechCrunch reports, and it reduced daily viewing time by about 50 million hours per day, or just over 2 minutes per day for each of the site's 1.4 billion daily active users (DAU).

Additionally, posts from brands have been de-emphasized in its news feed, CNBC adds, a change that is unlikely to be welcomed by advertisers. More worrying still, the number of daily active users in the U.S. and Canada declined for the first time ever, Barron's reports. The amount of users lost was about 700,000, per TechCrunch.

'Spots of Softness'

"MAU [monthly active user] growth and ad traction has been strong but showing spots of softness," Ives told Barron's. A study from eMarketer cited by Barron's projects that Facebook will have about 2 million fewer users under the age of 25 in the U.S. by the end of 2018, losing most of them to Snap. The same study forecasts that, for the first time, less than 50% of internet users in the U.S. between the ages of 12 and 17 will be on Facebook at least once a month.

Figures reported by TechCrunch indicate that Facebook's worldwide daily active users grew by 2.4% from the third quarter to the fourth quarter. This was the slowest growth rate between consecutive quarters during the past two years. Likewise, the 2.8% growth in global monthly active users also was the slowest over those same two years.

Declining Time Commitment

Market research firms ComScore and Nielsen find that U.S. users are spending less time on Facebook, per TechCrunch. "Overall, the results show how divorced Facebook's user behavior is from the day-to-day news coverage, blasting it for allowing Russian interference in U.S. elections and for making us unhealthy zombie browsers," TechCrunch asserts. (For more, see also: Facebook Is a Great Stock But Bad For Your Health.)

On the positive side, the average revenue per Facebook user worldwide was $6.18 in the fourth quarter of 2017, up 22% from the third quarter and 28% better than the fourth quarter of 2016, per data reported by TechCrunch. However, there is another dark cloud on the horizon, according to the same source. Facebook has warned investors that ad space in its news feed is running out.

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