age at the 1st intercourse

via chartsbin.com

Source

• Durex Network Research Unit 2009, Face of Global Sex report, 2005 - 2009, SSL International plc, Cambridge, viewed 20th October, 2009, <http://www.durexnetwork.org/en-GB/research>.
• Harris Interactive 2006, The Durex Sexual Wellbeing Global Survey, 2006, SSL International plc, Cambridge, viewed 20th October, 2009, <http://www.durex.com/en-US/SexualWellbeingSurvey>.
• more info from the same site