Year % 2000 4.428645909768606 2001 4.310401425507717 2002 4.20263010820986 2003 4.0250844177615575 2004 3.911779034368592 2005 3.8130917317106876 2006 3.7060415555580137 2007 3.654491881918123 2008 3.6301984664608042 2009 3.54728389246082 2010 3.46303640674566 2011 3.3047660130381455 2012 3.1895967202941975 2013 3.1136635169632623 2014 3.037882853368759 2015 2.9110773912751378 2016 2.825792218096194 2017 2.7454575249755395 2018 2.6674657843190714 2019 2.5806823245352764 2020 2.463393889163303