Year	%
2000	21.467668595204966
2001	21.30808239924764
2002	21.227529774057896
2003	20.805184868776465
2004	20.155216871511698
2005	20.100951673038075
2006	20.072754107896216
2007	19.996281435855785
2008	19.81172753867901
2009	19.539658926854905
2010	19.58530754282828
2011	19.527144599020204
2012	19.544627723457772
2013	19.22662825793963
2014	19.042263828816935
2015	19.375950916225435
2016	19.24926734119852
2017	18.920279639510916
2018	18.719951978565152
2019	18.58104165572323