Year	% of total
1970	91.20476047454572
1971	91.21847389656739
1972	91.06546044419275
1973	90.5632386324745
1974	90.08029285018507
1975	90.06923074139476
1976	83.27110363104569
1977	84.17619637411251
1978	84.06997966702232
1979	81.81406298859608
1980	81.0838826982715
1981	83.0464749964358
1982	82.61324962569827
1983	85.12354142545364
1984	88.02780660147867
1985	88.93525759718848
1986	88.98635101894345
1987	88.98419422953602
1988	89.57456495311392
1989	85.19059640088093
1990	95
1991	95
1992	95
1993	95.23809523809523
1994	90.9090909090909
1995	95.65217391304348
1996	95.83333333333334
1997	95.83333333333334
1998	96
1999	92.3076923076923
2000	92.3076923076923
2001	96.15384615384616
2002	96.15384615384616
2003	96.15384615384616
2004	96.15384615384616
2005	96.15384615384616
2006	92.3076923076923
2007	96.15384615384616
2008	96.15384615384616