Social ad revenue has been on a tear over the last few years, capping off 2013 with some big figures. Social channels drove a growing number of traffic to retail sites in Q4 2013, with revenue per visit (RPV) numbers up across the board: Tumblr jumped 340 percent year-over-year (YoY), followed by Pinterest (244 percent), Twitter (131 percent), and Facebook (72 percent).

The latest figures come from Adobe’s Social Media Intelligence Report, which noted Facebook is facing increased competition with share of referred visits to retail sites growing the fastest year-over-year for Twitter and Pinterest, up 125 percent and 89 percent respectively. It’s worth noting this contrasts quite a bit with Shareaholic’s Q4 2013 numbers, which show Facebook’s lead is not under threat.

social referred visits Adobe: Facebook ad click through rates up 365%, but Pinterest poised to post higher revenue per visitor in 2014

Traffic aside, Adobe says Facebook ads are becoming increasingly attractive to brand marketers due to growing consumer engagement. Facebook’s ad click-through rate (CTR) was up 365 percent year-over-year and Facebook cost per thousand impressions (CPMs) increased 437 percent. Meanwhile, Facebook’s cost-per-click (CPC) rates were flat year-over-year while ad click volume was up 125 percent.

social ad ctr cpc Adobe: Facebook ad click through rates up 365%, but Pinterest poised to post higher revenue per visitor in 2014

While Facebook is still referring more traffic than any other social site, Pinterest overtook Facebook for referring revenue in Q4 in the UK. Adobe believes Pinterest will surpass Facebook’s RPV in the US at some point this year.

social rpv yoy Adobe: Facebook ad click through rates up 365%, but Pinterest poised to post higher revenue per visitor in 2014

“We expect social ad revenue to continue to grow in 2014 as social media networks add more paid media capabilities and marketers allocate dollars across search, display and social,” Adobe Digital Index principal analyst Tamara Gaffney said in a statement. “Optimizing campaign spending across social channels and seeking a balance between CPCs and CPMs to drive ROI will become even more important.”

Adobe’s estimates are based on aggregated and anonymous data from retail, media, entertainment, and travel sites between Q4 2012 and Q4 2013. These include 500 million unique visitors to social networking sites, 240 billion Facebook ad impressions, more than 1.5 billion Facebook posts, and 6.3 billion social engagements on Facebook including comments, shares, and likes.

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