Year % 2000 16.25240141029023 2001 15.935099731234846 2002 15.70790808481876 2003 15.564275275182204 2004 15.44474321480429 2005 15.384067173912895 2006 15.331782939966942 2007 15.34709491256224 2008 15.309688386092047 2009 15.325528744465354 2010 15.344947028067665 2011 15.41535078679509 2012 15.482387066511578 2013 15.522085710260708 2014 15.615889093516076 2015 15.668198700480238 2016 15.789718338390935 2017 15.859002060970344 2018 15.959012336932052 2019 16.07195699917626