Year	Percent
1992	6.43505
1993	7.09482
1994	8.2918
1995	10.43181
1996	12.41712
1997	13.12418
1998	15.3564
1999	17.1996
2000	18.98438
2001	20.95652
2002	23.66571
2003	27.37925
2004	30.06446
2005	30.8436
2006	30.51443
2007	26.66237
2008	25.56531
2009	27.53404
2010	27.5127
2011	25.80795
2012	26.27401
2013	26.96549
2014	25.37228
2015	25.64819
2016	25.23614