Year	Percent
1960	15.72991
1961	21.04717
1962	25.65268
1963	20.71293
1964	16.21539
1965	14.74318
1966	15.88254
1967	17.57286
1968	29.63832
1969	34.87476
1970	27.8589
1971	31.26546
1972	22.00673
1973	9.68034
1974	10.59421
1975	6.17422
1976	12.9436
1977	8.87615
1978	25.07692
1979	17.93796
1980	13.48684
1981	29.03952
1982	20.33518
1983	14.53185
1984	8.15833
1985	6.60401
1986	11.89782
1987	21.4494
1988	26
1989	46.88063
1990	133.45121
1991	92.17987
1992	34.90422
1993	47.91792
1994	46.25048
1995	32.96404
1996	39.51538
1997	98.59568
1998	36.32503
1999	32.02542
2000	37.55228
2001	41.60998
2002	31.19994
2003	38.07624
2004	54.63183
2005	38.00287