Year	Percent
1990	0.8714
1991	0.9907
1992	1.65
1993	1.862
1994	1.72
1995	33.69
1996	40.09
1997	40.09
1998	39.63
1999	39.62
2000	40.07
2001	40.31
2002	40.77
2003	40.39
2004	40.91
2005	42.44
2006	42.55
2007	43.16
2008	41.56
2009	39.21
2010	39.61
