Year	Percent
1991	3.274
1992	1.617
1993	1.792
1994	2.977
1995	3.025
1996	3.017
1997	2.97
1998	2.919
1999	2.972
2000	2.868
2001	2.902
2002	2.843
2003	2.663
2004	2.707
2005	2.68
2006	2.685
2007	2.667
2008	2.688
2009	2.801
2010	2.694
2011	2.499
2012	2.505
2013	2.579
2014	2.549
2015	2.547
2016	2.481
2017	2.524
2018	2.526
2019	2.526
2020	2.528
2021	2.53
2022	2.531