The findings, based on four months of data (September 2013 through December 2013) sourced via analytics enabled on 200,000+ websites which reach 250+ million unique monthly visitors, lists the top referrers of social traffic with their respective share of overall traffic, starting with Facebook at the top.
- Facebook (15.44%)
- Pinterest (4.79%)
- Twitter (1.12%)
- StumbleUpon (0.86%)
- Reddit (0.21%)
- YouTube (0.19%)
- LinkedIn (0.05%)
- Google Plus (0.05%)
Note that these are share of overall visits for the month of December 2013.
Also, keep in mind that the social networks compete with search engines, paid campaigns and other sources for share of traffic. Shareaholic's Social Media Traffic Report also notes how much each social site's share of visits has changed since September. The increases and drops are shown both as a relative percentage, and in absolute percentage points.
For the full report, see it here.