Year	Percent
1991	5.5205
1992	6.24027
1993	5.55988
1994	5.30959
1995	4.63988
1996	5.27011
1997	4.83276
1998	4.43989
1999	4.31014
2000	4.23358
2001	4.19962
2002	4.03998
2003	4.55974
2004	3.41025
2005	3.51555
2006	3.60996
2007	3.01005
2008	2.77972
2009	2.93968
2010	2.84007
2011	3.27016
2012	2.77991
2013	2.7116
2014	2.71928
2015	2.8926
2016	2.85794
2017	2.7601
2018	2.69777
2019	2.65095