Year Number 1950 67.251 1951 69.203 1952 72.465 1953 74.825 1954 75.696 1955 75.548 1956 78.136 1957 78.618 1958 78.468 1959 78.931 1960 80.394 1961 81.11 1962 83.509 1963 86.684 1964 89.255 1965 90.65 1966 92.581 1967 93.377 1968 93.545 1969 93.859 1970 94.637 1971 96.354 1972 97.903 1973 99.37 1974 100.725 1975 101.89 1976 102.694 1977 103.56 1978 104.216 1979 104.328 1980 103.793 1981 103.958 1982 103.524 1983 102.674 1984 101.71 1985 100.782 1986 100.452 1987 100.176 1988 99.87 1989 99.426 1990 98.822 1991 97.482 1992 96.007 1993 94.505 1994 93.114 1995 91.9 1996 90.645 1997 89.602 1998 88.677 1999 87.726 2000 86.681 2001 86.1 2002 85.307 2003 84.435 2004 83.674 2005 83.106 2006 82.711 2007 82.614 2008 82.634 2009 82.544 2010 82.275 2011 81.709 2012 80.878 2013 79.978 2014 79.229 2015 78.696 2016 78.478 2017 78.393 2018 78.324 2019 78.106 2020 77.664 2021 77.125 2022 76.437 2023 75.636 2024 74.779 2025 73.905 2026 73.106 2027 72.286 2028 71.473 2029 70.708 2030 70.016 2031 69.48 2032 68.991 2033 68.541 2034 68.12 2035 67.723 2036 67.428 2037 67.136 2038 66.851 2039 66.575 2040 66.309 2041 66.102 2042 65.886 2043 65.659 2044 65.413 2045 65.144 2046 64.893 2047 64.611 2048 64.304 2049 63.983 2050 63.655 2051 63.352 2052 63.034 2053 62.702 2054 62.36 2055 62.012 2056 61.691 2057 61.357 2058 61.019 2059 60.689 2060 60.374 2061 60.11 2062 59.854 2063 59.602 2064 59.344 2065 59.076 2066 58.841 2067 58.588 2068 58.334 2069 58.1 2070 57.898 2071 57.744 2072 57.608 2073 57.491 2074 57.387 2075 57.296 2076 57.238 2077 57.183 2078 57.133 2079 57.088 2080 57.048 2081 57.021 2082 56.992 2083 56.961 2084 56.93 2085 56.902 2086 56.875 2087 56.845 2088 56.817 2089 56.793 2090 56.777 2091 56.763 2092 56.751 2093 56.745 2094 56.752 2095 56.776 2096 56.793 2097 56.824 2098 56.871 2099 56.935 2100 57.015