After a 31 percent decline in Facebook's shares since an initial public offering in May, through yesterday, investors are looking for signs that the company can extract more ad dollars from promotions on mobile phones. The number of daily Facebook users on desktops and laptops fell in the fourth quarter as the portion of members on mobile devices increased, regulatory filings show.
Facebook's nascent mobile-ad service, started in March 2012, isn't helping the company gain market share in the U.S., according to EMarketer Inc. Facebook is projected to grab 12 percent of the market in 2015, down from 13 percent this year, EMarketer said. Over the same period, Google's stake will climb about two percentage points to 57 percent.
With assistance from Adam Satariano, Tom Giles and Douglas MacMillan in San Francisco.