Year	% of total
1990	81.55893536121674
1991	80.33126293995859
1992	76.57430730478589
1993	76.68393782383419
1994	77.00258397932816
1995	80.27522935779817
1996	80.76923076923077
1997	82.22698072805139
1998	81.42201834862385
1999	81.37254901960785
2000	80.32786885245902
2001	80.3357314148681
2002	77.96610169491525
2003	74.68030690537084
2004	78.48605577689243
2005	75.52301255230127
2006	74.61368653421634
2007	74.7011952191235
2008	70