Year	%
2000	18.723348404161275
2001	18.362335522760237
2002	18.14652795842204
2003	17.996981824481995
2004	17.764506606653487
2005	17.30290059953651
2006	17.03592695470139
2007	16.816057611567576
2008	16.776730778694755
2009	16.544763295488277
2010	16.35912767733845
2011	16.10948333969112
2012	15.92711276802184
2013	15.698851524179615
2014	15.533411850432955
2015	15.519712247848359
2016	15.617552420386637
2017	15.257771158858072
2018	15.107458843048242
2019	14.94365508548031