Year	Percent
1984	11.75809
1985	10.17188
1986	9.61029
1987	8.62786
1988	6.6461
1989	6.63914
1990	8.98079
1991	9.2019
1992	9.04226
1993	9.83197
1994	10.49516
1995	9.57877
1998	13.55213
1999	16.06661
2000	19.19472
2001	21.68858
2002	25.71596
2003	28.4708
2004	37.23656
2005	43.29425
2006	48.82515
2007	50.14123
2008	43.84995
2009	49.20489
2010	48.08985
2012	55.44996
2013	56.03388
2014	57.4077