Year	% of total
1960	61.75637393767705
1961	63.68421052631579
1962	72.11895910780669
1963	64.07322654462241
1964	68.99641577060932
1965	68.53932584269663
1966	68.48030018761726
1967	66.78023850085178
1968	68.53766617429838
1969	69.94535519125682
1970	69.4980694980695
1971	68.84057971014494
1972	68.49162011173185
1973	67.12328767123287
1974	66.7644183773216
1975	68.62037871956717
1976	68.69275603663614
1977	70.94395280235987
1978	69.68928344958782
1979	70.8381839348079
1980	71.42857142857142
1981	68.2671081677704
1982	66.64859002169197
1983	67.50524109014674
1984	85.10517339397386
1985	73.03005686433794
1986	72.93404094010614
1987	72.70523034291652
1988	74.69955724225173
1989	74.323386537127
1990	56.37623747108712
1991	68.96742547425475
1992	71.57208398133749
1993	64.1492911392405
1994	65.94914728682171
1995	66.5981420233463
1996	78.69913693901036
1997	76.61103286384977
1998	75.31288888888889
1999	73.2122299651568
2000	68.2062
2001	70.88715719063545
2002	70.62794791666667
2003	68.6134693877551
2004	71.11525104602511
2005	61.636103074141054
2006	59.4042190016103
2007	73.56531490015361
2008	72.06771781033154
2009	78.09849706744868
2010	78.18320754716981
2011	115.81472345835981
2012	183.32860560093349
2013	216.6482752992383
2014	143.68487858719647
2015	113.9313583815029
2016	121.63461199779857