Year	Percent
1973	26.72
1974	5.416
1981	31.83
1983	11.63
1984	5.636
1986	40
1988	10.73
1989	14.36
1990	3.588
1991	14.29
1992	11.67
1993	11.51
1994	12.42
1995	11.48
1996	16.18
1997	9.905
1998	6.627
1999	8.813
2000	9.847
2001	5.158
2002	9.013
2003	6.083
2004	2.019
2005	8.975
2006	11.17
2007	8.08