Year	Percent
1983	4.0172
1984	6.4647
1985	6.3686
1986	7.7225
1987	6.0592
1988	6.8852
1989	5.453
1990	5.0044
1991	3.9551
1992	4.1452
1993	3.6743
1994	5.9322
1995	4.3997
1996	3.9956
1997	4.3047
1998	5.4085
1999	8.1129
2000	2.8477
2002	3.8299
2003	1.3368
2004	2.8334
2005	5.4816
2006	5.6612
2007	5.3304
2008	5.5552
2009	5.2384
2010	5.2405
2011	4.2368
2012	5.0735
2013	5.298
2014	5.1259
2015	4.7272
2016	6.0287
2017	6.5484