Year	Percent
1973	5.742
1974	11.09
1975	14.21
1976	1.906
1977	1.665
1978	1.182
1979	1.383
1980	2.851
1981	5.453
1982	8.427
1983	3.701
1984	10.07
1985	11.16
1986	16.37
1988	8.009
1989	12.41
1990	7.607
1991	1.633
1992	3.315
1993	2.255
1994	12.49
1995	6.146
1996	7.811
1997	3.676
1998	13.64
1999	12.07
2000	7.563
2001	6.921
2002	15.74
2003	11.11
2004	5.871
2005	5.757
2006	12.23
2007	5.426