Year	Percent
1991	16.114
1992	14.687
1993	10.748
1994	8.181
1995	7.647
1996	7.759
1997	6.914
1998	6.283
1999	4.61
2000	3.684
2001	4.05
2002	2.574
2003	3.778
2004	3.326
2005	4.733
2006	4.639
2007	3.823
2008	4.762
2009	4.756
2010	5.294
2011	6.589
2012	5.034
2013	4.509
2014	4.093
2015	3.889
2016	4.026
2017	4.092
2018	4.024
2019	3.949
2020	3.876
2021	3.84
2022	3.762