Year	Percent
1991	1.477
1992	5.765
1993	5.147
1994	13.06
1995	8.479
1996	7.11
1997	9.816
1998	9.227
1999	20.09
2000	15.23
2001	14.77
2002	15.75
2003	14.52
2004	11.84
2005	9.319
2006	10.26
2007	16.94