Year	Percent
1990	33.51528
1991	11.30446
1992	9.41503
1993	8.94147
1994	8.87345
1995	8.20859
1996	8.41749
1997	8.3583
1998	8.74815
1999	8.45657
2000	8.16766
2001	7.70206
2002	6.88819
2003	6.6693
2004	2.68002
2005	3.29125
2006	7.10391
2007	5.22189
2008	8.15238
2009	8.9748
2010	10.57328
2011	10.21555
2012	9.77694
2013	2.01186
2014	2.22674
2015	2.15263
2016	2.0847
2017	2.0857
2018	3.23369
2019	3.18739
2020	4.30447