Year	Percent
1991	2.207
1992	2.077
1993	2.037
1994	2.135
1995	2.139
1996	2.047
1997	2.038
1998	1.909
1999	1.943
2000	2.063
2001	1.961
2002	2.099
2003	2.04
2004	2.16
2005	2.155
2006	2.255
2007	2.281
2008	2.397
2009	2.526
2010	2.561
2011	2.291
2012	2.075
2013	2.113
2014	2.171
2015	2.166
2016	2.191
2017	2.324
2018	2.315
2019	2.297
2020	2.291
2021	2.291
2022	2.297