Year % of total 1960 100 1961 100 1962 100 1963 100 1964 100 1965 100 1966 100 1967 100 1968 100 1969 100 1970 100 1971 100 1972 100 1973 100 1974 100 1975 100 1976 100 1977 100 1978 100 1979 100 1980 100 1981 100 1982 100 1983 100 1984 100 1985 100 1986 100 1987 100 1988 100 1989 100 1990 134.45666666666665 1991 121.67772727272725 1992 91.04275862068965 1993 108.5432 1994 107.07639999999998 1995 101.86111111111111 1996 104.77142857142859 1997 102.67600000000002 1998 96.67545454545454 1999 100.00909090909089 2000 104.4539393939394 2001 99.53285714285714 2002 94.96589743589745 2003 98.38292682926829 2004 105.42624999999998 2005 104.64365853658538 2006 100.84249999999999 2007 102.03826086956522 2008 100.07854166666668 2009 36.67 2010 107.01653061224489 2011 100.66274509803921 2012 72.83069444444445 2013 111.57042553191489 2014 110.01 2015 111.50673469387755 2016 111.4768