Year % 2000 10.3141469521754 2001 9.90073278317987 2002 8.74071171855736 2003 8.5193328742632 2004 7.62136518703205 2005 7.42053350400126 2006 6.89916880302373 2007 6.39246550222868 2008 5.26217135392772 2009 4.91061927693344 2010 4.59298562645994 2011 3.77597206599782 2012 3.47642064778055 2013 3.31073756286639 2014 3.03286971899675 2015 2.89751656370217 2016 2.33780069608712 2017 2.40871284435385 2018 2.14481248465872 2019 1.88776446065724 2020 1.92301883746688