Year	% of total
1981	78.17164179104478
1982	81.99233716475096
1983	85.96112311015118
1984	88.8421052631579
1985	95.27720739219713
1986	91.62479061976549
1987	94.48123620309052
1988	84.15841584158416
1989	86.91037735849056
1990	88.0794701986755
1991	96.47058823529412
1992	97.33096085409252
1993	97.06405693950177
1994	97.51838235294117
1995	97.98270893371757
1996	97.22589167767504
1997	96.87092568448502
1998	97.87234042553192
1999	97.60850310008857
2000	97.63157894736842
2001	97.8742249778565
2002	97.4694589877836
2003	97.2168905950096
2004	94.76386036960986
2005	99.42965779467681
2006	99.38962360122076
2007	99.27536231884058
2008	100
2009	100
2010	100
2011	91.42259414225941
2012	71.42857142857143
2013	82.34019501625134
2014	95.67661046260268
2015	96.35995955510617