Year	Percent
1988	7.20783
1989	7.24386
1990	7.79216
1991	8.19796
1992	8.55383
1993	8.5796
1994	8.37735
1995	8.13018
1996	7.89513
1997	7.61419
1998	8.09409
1999	8.28327
2000	9.47651
2001	9.56415
2002	9.19076
2003	8.02563
2004	8.03739
2005	7.98053
2006	7.33481
2007	6.26434
2008	6.40488
2009	7.46891
2010	7.24313
2011	7.3662
2012	7.07125
2013	7.24438
2014	7.23986
2016	7.48838