Year	% of total
1990	89.63231602750189
1991	81.31405962062493
1992	90.2233030198666
1993	87.34650999597676
1994	86.27082462997082
1995	91.10049043632732
1996	92.42609622376627
1997	90.29472186070292
1998	82.47504584307136
1999	78.07855636417494
2000	76.45768696687531
2001	80.01132404362824
2002	79.11348751684406
2003	81.25177760860687
2004	83.211023955653
2005	79.48436300252415
2006	77.00631647441156
2007	78.68624500411148
2008	76.59705499789798
2009	73.86102775431299
2010	74.83055415423134
2011	73.39486764740106
2012	75.0350707539599
2013	75.55292173686914
2014	77.2000564292393
2015	77.25693528222355
2016	74.92852151284205