Year	Percent
1991	1.76941
1992	1.71451
1993	1.66156
1994	1.61185
1995	1.59846
1996	1.58724
1997	1.12237
1998	1.68018
1999	1.63163
2000	1.58546
2001	2.53866
2002	2.46945
2003	2.4057
2004	2.34474
2005	2.28175
2006	2.21786
2007	2.15652
2008	2.09809
2009	2.07023
2010	2.01846
2011	1.97089
2012	1.92546
2013	1.76177
2014	1.75278
2015	1.72476
2016	1.77641
2017	1.7788
2018	1.76048
2019	1.74163
2020	1.73223