Annual % of total
1960 50.86887835703001
1961 52.255054432348366
1962 56.82967959527825
1963 58.94568690095847
1964 46.567717996289424
1965 47.3293768545994
1966 56.70731707317073
1967 52.16
1968 73.66702937976062
1969 71.28514056224901
1970 63.24324324324324
1971 62.74752475247525
1972 63.95631067961165
1973 65.67164179104478
1974 66.0500544069641
1975 69.6489241223103
1976 64.76906552094522
1977 67.50788643533123
1978 69.53367875647668
1979 74.12109375000001
1980 69.63350785340313
1981 70.67961165048543
1982 64.31980906921241
1983 73.58834244080145
1984 72.43293246993524
1985 71.29909365558912
1986 68.62106406080348
1987 71.55090390104662
1988 70.71167883211679
1989 75.62604340567614
1990 99.74701257861635
1991 174.28787356321837
1992 185.08439189189187
1993 182.06783216783217
1994 127.485546875
1995 162.05774193548388
1996 177.18944
1997 152.1805
1998 120.48714285714286
1999 95.00863636363637
2000 89.68206521739131
2001 87.2653164556962
2002 84.59102272727273
2003 84.64943925233645
2004 84.62307692307692
2005 83.18429530201342
2006 82.965875
2007 82.76942857142858
2008 86.08625668449199
2009 76.7778125
2010 83.84257281553398
2011 88.18261904761906
2012 90.5432098765432
2013 92.22756164383561
2014 94.00993736951983
2015 91.23089965397924
2016 92.92106796116505