Year	Percent
1980	19.86925
1981	20.53526
1982	21.46057
1983	19.39411
1984	26.36583
1985	27.53485
1986	43.67781
1987	39.18984
1988	32.90459
1989	41.43513
1990	51.70729
1991	71.04661
1992	55.09155
1993	66.49766
1994	57.17325
1995	53.47247
1996	50.23937
1997	61.90727
1998	46.08051
1999	46.62271
2000	22.042
2001	18.91308
2002	18.55054
2003	19.87525
2004	15.89185
2005	18.29189
2006	21.95469
2007	27.25617
2008	14.63215
2009	17.4931
2010	9.93855
2011	9.63587
2012	13.06261
2013	16.50956
2014	12.81949
2015	8.75434
2016	4.17333
2017	8.44494
2018	7.73397
2019	14.17173
2020	21.08311
2021	10.32654