Year	Percent
1991	5.53
1992	3.676
1993	3.659
1994	3.805
1995	3.928
1996	3.69
1997	3.71
1998	3.41
1999	3.414
2000	3.596
2001	3.737
2002	4.241
2003	4.143
2004	4.385
2005	4.064
2006	4.099
2007	3.903
2008	3.826
2009	3.731
2010	3.785
2011	4.109
2012	3.881
2013	3.823
2014	3.743
2015	3.51
2016	3.268
2017	3.107
2018	3.114
2019	3.118
2020	3.119
2021	3.115
2022	3.11
