Year	% of total
1990	75.75342626923339
1991	77.72702808525558
1992	65.0571060502823
1993	61.01380458732325
1994	66.80929516130799
1995	59.97047249742079
1996	58.61733395132378
1997	60.17216696576809
1998	59.25243502307539
1999	60.26766648663846
2000	58.67376982670622
2001	57.443716376739054
2002	53.45321368539062
2003	52.159059038666165
2004	53.3631103036763
2005	59.880211094319925
2006	61.14546617706825
2007	60.97062019751601
2008	60.250677320272416
2009	55.37100449456922
2010	74.29750941702342
2011	73.87595172744493
2012	72.89319445483736
2013	70.02233644461592
2014	67.99374947056347