Identify suitable metrics
+Discussion
Let's get the CSR reports first of the three companies to see what they report on.
Easyjet: http://corporate.easyjet.com/corporate-responsibility.aspx?sc_lang=en. They don't seem to have a downloaded pdf report. Ugh.
Ryanair: https://investor.ryanair.com/wp-content/uploads/2016/07/Ryanair-Annual-Report-FY16.pdf. Couldn't find a dedicated CSR report. Ugh.
Turkish Airlines: http://investor.turkishairlines.com/documents/ThyInvestorRelations/download/icerikler/THY_2015_Sustainability_Report_vF.pdf. They got one!
Let's look at CO2 emissions first
Seems the companies are not reporting on the same basis. Found an interesting link in the Turkish Airline report. Will create that metric shown in this report. http://www.theicct.org/sites/default/files/publications/ICCT_transatlantic-airline-ranking-2014.pdf. Covers 20 companies, but not easyjet or Ryanair, but still will add for possible future use.