Year	Percent
1991	5.531
1992	5.409
1993	5.282
1994	5.616
1995	4.619
1996	4.279
1997	4.37
1998	3.907
1999	3.573
2000	3.058
2001	3.303
2002	3.221
2003	3.284
2004	3.488
2005	3.313
2006	2.239
2007	1.734
2008	2.213
2009	2.436
2010	2.62
2011	2.686
2012	2.753
2013	2.769
2014	4.982
2015	5.029
2016	5.044
2017	5.129
2018	5.246
2019	5.277
2020	5.28
2021	5.269
2022	5.261