Annual % 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