Annual % of total
1960 100
1961 100
1962 100
1963 100
1964 98.18181818181819
1965 97.23502304147465
1966 95.31772575250837
1967 96.70329670329672
1968 95.45454545454545
1969 95.42168674698796
1970 94.98861047835989
1971 93.58974358974359
1972 93.4873949579832
1973 94.26086956521739
1974 92.67734553775743
1975 94.91833030852995
1976 94.6788990825688
1977 94.59459459459458
1978 95.55895865237368
1979 95.3674121405751
1980 95.82689335394127
1981 95.30685920577618
1982 95.69471624266144
1983 94.13333333333334
1984 96.4622641509434
1985 98.39449541284404
1986 98.54166666666666
1987 98.54166666666666
1988 98.63281250000001
1989 98.61660079051384
1990 98.62965517241379
1991 99.1179207920792
1992 98.99093596059114
1993 98.86519607843137
1994 98.86519607843137
1995 98.79538834951455
1996 98.90322115384615
1997 99.00899999999999
1998 99.00899999999999
1999 98.93981132075471
2000 146.43222972972973
2001 153.19375
2002 136.20285714285714
2003 121.93520325203254
2004 109.21856115107913
2005 92.00047337278107
2006 111.44803921568626
2007 122.23333333333332
2008 130.10315068493153
2009 135.55255172413794
2010 136.1426436781609
2011 90.07656410256409
2012 90.02184426229508
2013 88.71257641921397
2014 81.95189393939395
2015 59.60541818181818
2016 71.59380952380953