Facebook’s mobile-only users are increasing with each passing quarter. It said in a form 10-Q report filed with the Securities and Exchange Commission on Wednesday that roughly 126 million of its mobile monthly active users accessed the social network exclusively through mobile devices in September.

The new number, up 24 percent from June, means that now nearly 21 percent of Facebook’s 604 million mobile monthly active users are skipping the website altogether.

“While most of our mobile users also access Facebook through personal computers, we anticipate that the rate of growth in mobile usage will exceed the growth in usage through personal computers for the foreseeable future and that the usage through personal computers may be flat or continue to decline in certain markets, including key developed markets such as the United States, in part due to our focus on developing mobile products to encourage mobile usage of Facebook,” the company disclosed in the 10-Q report.

Cue the overly dramatic gasps — except maybe not. Three months ago, these numbers would have given investors and analysts full-blown panic attacks. Then, the social network had not yet demonstrated that it could monetize the attention of its members switching to mobile in any meaningful fashion.

After yesterday’s earnings report, in which the company showed for the first time that Sponsored Stories in mobile News Feed could really bring home the bacon, the mobile-only user figure doesn’t seem so scary. Facebook said yesterday that it made 14 percent of its advertising revenue, or more than $150 million, from mobile during the third quarter. It also said that by the end of the quarter it was pulling in as much as $3 million per day from mobile News Feed ads. The stock price, as a result, is now in recovery mode.

“Exiting 3Q, [Facebook’s mobile advertising] run rate had nearly doubled and had an annualized run rate in excess of $1B ($3M a day) — quite impressive given [Facebook] began showing mobile ads only at the end of 1Q this year,” Sterne Agee analysts Arvind Bhatia and Brett Strauser wrote in their post-earnings report. “We feel this was the single biggest take-away from 3Q earnings.”

Facebook’s stock, which had been hovering in the mid $19s, closed Wednesday up 19 percent at $23.23 a share.

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