The pie charts illustrate the proportions of particular apps' users such as Twitter, Facebook, and Google+ across age groups from 2011 to 2013.
In general, Facebook remained the most popular application, though it's share reduced over the given period. In addition, all the other social media channels had seen notable increase, especially Google+ and LinkedIn. To begin with, Facebook decreased from 59% to 38% within two years.
As for the Twitter, with 2% yearly growth it comprised 25% in 2013. Lastly, LinkedIn accounted for 10%, 12%, 15% in 2011, 2012, 2013, respectively. Moving to, Google+ and Pinterest both made up 5% in 2011.
In contrast, Google+ enlarged as twice as in 2011 (10%), whereas Pinterest only rose to 6% in 2012. Finally, in 2013, Google+ represented 14% compared to Pinterest that constituted 8%.