Yearly traffic* broken down by search, direct, referral, 'not set', and social (Suppl. material 14). Search makes up the lion-share of all traffic. Direct traffic is second in size overall due to people that type or bookmark. Referrals are web links posted on other websites that directly refer a web user to another site. 'Not set' is a difficult parameter to define but is probably due to: individuals blocking JS as a security measure; those using private browser settings; use of browser plugins that block JS; or may also be the result of improper GA usage by referring sites. Interestingly, social traffic remains below one percent of all traffic when examined across the entire sample. *Caveat: this data was derived from 'Acquisition, Channels' which only became available on July 25, 2013, creating an 11 month data set.

  Part of: Jones T, Baxter D, Hagedorn G, Legler B, Gilbert E, Thiele K, Vargas-Rodriguez Y, Urbatsch L (2014) Trends in access of plant biodiversity data revealed by Google Analytics. Biodiversity Data Journal 2: e1558.