Year	%
2000	18.741075362179078
2001	18.45205720649388
2002	18.660943018559934
2003	18.753364311209953
2004	18.57992463126132
2005	17.879111079787204
2006	17.18340061434768
2007	16.624662386731394
2008	16.141057049832366
2009	15.732312549342174
2010	15.373997572771628
2011	15.011191329880502
2012	14.556673824512902
2013	14.129160497188515
2014	13.858832807105221
2015	13.639689602052826
2016	13.474998312888058
2017	13.349320855578343
2018	13.241314579004776
2019	13.140207538851579