Year	%
1990	71.67
1992	49.21
1996	32.67
1997	27.81
1999	30.62
2000	32.2
2001	32.89
2002	29.94
2003	28.95
2004	30.6
2005	25.44
2006	20.27
2007	24.22
2008	17.57
2009	17.67
2010	16.48
2011	19.01
2012	19.63
2013	19.57
2015	18.4
2016	16.64
2017	16.67
2018	16.84
2019	19.39
2020	17.56
2021	17.15