Year	Percent
1990	8.63919
1991	7.45061
1992	5.60078
1993	5.91191
1994	7.67825
1995	8.42952
1996	8.95249
1997	10.52276
1998	11.26215
1999	10.88482
2001	8.08387
2002	9.70983
2003	9.1169
2004	9.68076
2005	8.72442
2006	8.26285
2007	7.81253
2008	7.81414
2009	6.58118
2010	8.16344
2011	9.20936
2012	9.37759
2013	8.76473