Dive Brief: 

• Social plugin service Shareaholic's report of referral traffic from the top social media sites put Facebook, Pinterest and Twitter in the top three spots with a growth of 58.81%, 66.52% and 54.12% over the last year respectively. 
• StumbleUpon and Reddit are still ranked at 4th and 5th place for referral traffic, but both were on the decline in the past year —​ StumbleUpon's referral traffic fell over 27%, while Reddit's fell a whopping nearly 35% in the past year. 
• YouTube and LinkedIn are still trailing StumbleUpon and Reddit, but their ability to generate referral traffic is growing quickly. YouTube grew nearly 53% and LinkedIn increased referral traffic by over 34%. 

Dive Insight: 

At first glance, it seems obvious that marketers should turn their attention to the social networks with the highest level of referral traffic, and, on some level, this assessment is true. What is important to note, however, is that, even though StumbleUpon and Reddit have declined in referrals, the top three sites are still outperforming a wide variety of social networks including the fast-growing YouTube and LinkedIn. The type of referral traffic each site provides may be a better measure for marketing campaigns.