Year	Percent
1991	2.597
1992	2.597
1993	2.612
1994	2.917
1995	3.087
1996	3.371
1997	3.006
1998	3.483
1999	3.296
2000	3.495
2001	4.118
2002	4.095
2003	4.405
2004	4.462
2005	3.894
2006	6.125
2007	6.192
2008	6.679
2009	7.405
2010	7.085
2011	6.691
2012	6.585
2013	6.13
2014	5.84
2015	5.347
2016	5.264
2017	4.99
2018	4.749
2019	4.615
2020	4.473
2021	4.345
2022	4.243