Year	%
2000	19.837578075977607
2001	19.581535636515955
2002	19.60872001211925
2003	19.441188425334975
2004	19.030498499140933
2005	18.66157279045783
2006	18.30749307152186
2007	18.00414258961164
2008	17.698163026110922
2009	17.35565440111589
2010	17.230754758308365
2011	17.037708028926478
2012	16.81316649477901
2013	16.46343641382703
2014	16.248312721221346
2015	16.31484713215316
2016	16.18938093652702
2017	15.953459733901214
2018	15.809849948485411
2019	15.698916729429415