Year	Percent
1967	41.97
1968	65.63
1975	7.634
1977	11.14
1978	6.122
1979	8.826
1980	0.2247
1981	16.56
1982	25.08
1983	28.85
1984	25.89
1985	31.81
1986	32.16
1987	26.75
1988	25.82
1989	28.25
1990	27.79
1991	38.01
1992	32.15
1993	26.24
1994	45.19
1995	43.53
1996	19.21
1997	44.4
1998	5.408
1999	9.473
2000	6.066
2001	9.855
2002	3.957
2003	6.569
2004	6.122
2005	40.2
2006	36.09
2007	15.37