Year % of total 1960 91.02564102564104 1961 92.5925925925926 1962 90.36144578313252 1963 89.70588235294117 1964 90.24390243902438 1965 92.7710843373494 1966 93.97590361445783 1967 92.95774647887323 1968 91.66666666666666 1969 91.86046511627906 1970 92.38095238095238 1971 90.9090909090909 1972 89.71962616822428 1973 86.95652173913044 1974 85.27131782945736 1975 84.0909090909091 1976 82.06521739130434 1977 82.90155440414509 1978 83.49514563106796 1979 84.46601941747572 1980 83.90243902439025 1981 84.688995215311 1982 75.1111111111111 1983 71.31147540983605 1984 70.68273092369479 1985 68.8715953307393 1986 79.56521739130436 1987 81.12449799196789 1988 79.92831541218638 1989 86.21908127208481 1990 85.9228431372549 1991 80.3073 1992 81.4888888888889 1993 91.67500000000001 1994 96.5 1995 97.37922222222223 1996 96.17226415094339 1997 106.25637795275588 1998 94.05435114503817 1999 95.12942028985508 2000 91.30081632653062 2001 91.675 2002 91.9755737704918 2003 87.92696132596686 2004 110.00999999999999 2005 112.58333333333333 2006 114.48715116279071 2007 110.1897549019608 2008 110.7325615763547 2009 106.50884422110552 2010 80.3460569105691 2011 73.86385714285714 2012 86.5412 2013 82.60824175824175 2014 88.55924836601308 2015 85.3792469879518 2016 84.6645588235294