Year	% of total
1992	61.02295364756504
1993	65.38629631325853
1994	68.23021524023258
1995	64.27455009276439
1996	65.58034422948631
1997	65.07544199984228
1998	63.635056015960714
1999	65.82303763213531
2000	65.30764562260202
2001	72.24517743809778
2002	68.1411081837642
2003	65.90645561261923
2004	70.37896218878977
2005	66.05023510585919
2006	64.00208146051828
2007	64.91468404632225
2008	56.92614068359123
2009	59.6287023797865
2010	58.692994587824856
2011	59.34214088112639
2012	59.59007867820614
2013	55.56147304361395
2014	68.56752180480437
2015	62.948037166085946
2016	60.14162810510268