Year % (cumulative) 1970 5.55979 1980 6.42121 1991 12.28359 2003 12.00774 2006 13.82981 2008 15.18693 2009 15.28482 2010 15.8321 2011 16.1243 2012 15.68907 2013 16.30318 2014 15.67415 2015 15.59705 2016 17.07514