Year	Percent
1991	7.86329
1992	7.66379
1993	7.45021
1994	7.24868
1995	7.05878
1996	6.86589
1997	6.67442
1998	6.46351
1999	6.26376
2000	6.12306
2001	6.03328
2002	4.66
2003	4.4848
2004	4.31147
2005	4.14544
2006	3.98079
2007	4.29
2008	4.29
2009	4.06
2010	4.15827
2011	4.25639
2012	4.35476
2013	4.45045
2014	5.26052
2015	6.1
2016	4.97
2017	3.5582
2018	2.52
2019	2.41071