Year	%
1992	34.67
1993	30.9
1994	29.25
1996	23.71
1997	17.09
1998	16.78
1999	16.67
2000	17.39
2001	16
2002	12.23
2003	10.75
2004	9.78
2005	8.78
2006	8.85
2007	8.86
2008	8.68
2009	8.02
2010	8.19
2011	8
2014	7.55
2015	7.78
2016	8.17
2017	9.08
2018	7.98
2019	6.48
2020	6.51
2021	6.43