Annual % of total
1960 30.519480519480517
1961 16.012558869701728
1962 14.735336194563661
1963 15.340086830680175
1964 20.64516129032258
1965 13.931034482758623
1966 3.1680440771349856
1967 12.56218905472637
1968 3.506787330316742
1969 1.4431239388794568
1970 1.6309887869520896
1971 1.146788990825688
1972 0.10351966873706003
1973 0.5964214711729622
1974 0.75
1975 0.37974683544303794
1976 0.39215686274509803
1977 0.12562814070351758
1978 0.8501594048884166
1979 0.09578544061302681
1980 0.10752688172043011
1981 0.09090909090909091
1982 1.9559902200488997
1983 1.5765765765765765
1984 0.18885741265344663
1985 0.18535681186283595
1986 0.09900990099009901
1987 0
1988 0
1989 0.10526315789473684
1990 0.09549479166666666
1991 0.1842713567839196
1992 0.06984761904761905
1993 0.07204322200392926
1994 0.12710571923743502
1995 0.06300687285223368
1996 0.04386363636363636
1997 0.08793764988009592
1998 0.04259001161440185
1999 0.0386
2000 0.03354986276303751
2001 0.03379723502304147
2002 0.0322231985940246
2003 1.8615713134568896
2004 1.795034965034965
2005 1.6525107296137338
2006 1.8320225624496373
2007 1.1872553348050037
2008 1.7175644028103045
2009 1.820073230268511
2010 1.7395103289977047
2011 7.348268482490273
2012 11.417159833630421
2013 13.953846685082874
2014 22.064505681818183
2015 25.64738703339882
2016 25.215850433196536