Year	Percent
1996	34.11
1997	25.86
1998	26.98
1999	23.55
2000	21.27
2001	24.19
2002	25.29
2003	20.44
2004	21.82
2005	15.15
2006	13.62
2007	10.55
2008	13.62
2009	33.34
2010	36.15
2011	31
2012	28.53
2013	23.22
2014	19.62
2015	16.33
2016	17.29
2017	16.99
2018	12.2
2019	12.42
2020	14.87