Year Number 1950 73.696 1951 74.16 1952 74.052 1953 73.633 1954 73.024 1955 72.242 1956 72.594 1957 72.664 1958 72.447 1959 71.953 1960 71.224 1961 71.827 1962 71.962 1963 71.776 1964 71.436 1965 71.026 1966 71.799 1967 72.306 1968 72.605 1969 72.742 1970 72.768 1971 73.876 1972 74.756 1973 75.47 1974 76.058 1975 76.548 1976 78.016 1977 79.19 1978 80.152 1979 80.988 1980 81.734 1981 83.24 1982 84.502 1983 85.533 1984 86.357 1985 87.02 1986 88.305 1987 89.288 1988 89.963 1989 90.198 1990 89.812 1991 90.529 1992 90.768 1993 90.507 1994 89.897 1995 89.172 1996 89.216 1997 88.915 1998 88.422 1999 87.922 2000 87.634 2001 87.813 2002 87.699 2003 87.453 2004 87.092 2005 86.517 2006 86.692 2007 86.731 2008 86.542 2009 86.08 2010 85.371 2011 85.158 2012 84.62 2013 83.841 2014 82.925 2015 81.925 2016 81.044 2017 80.132 2018 79.137 2019 77.987 2020 76.673 2021 75.664 2022 74.454 2023 73.125 2024 71.787 2025 70.5 2026 69.456 2027 68.428 2028 67.403 2029 66.349 2030 65.261 2031 64.379 2032 63.453 2033 62.499 2034 61.542 2035 60.6 2036 59.866 2037 59.113 2038 58.35 2039 57.586 2040 56.828 2041 56.24 2042 55.637 2043 55.024 2044 54.407 2045 53.793 2046 53.331 2047 52.854 2048 52.363 2049 51.863 2050 51.36 2051 50.995 2052 50.605 2053 50.198 2054 49.781 2055 49.361 2056 49.061 2057 48.744 2058 48.417 2059 48.089 2060 47.765 2061 47.578 2062 47.375 2063 47.164 2064 46.955 2065 46.759 2066 46.697 2067 46.623 2068 46.546 2069 46.47 2070 46.404 2071 46.473 2072 46.527 2073 46.566 2074 46.584 2075 46.584 2076 46.692 2077 46.761 2078 46.803 2079 46.829 2080 46.849 2081 46.994 2082 47.111 2083 47.204 2084 47.276 2085 47.333 2086 47.52 2087 47.669 2088 47.787 2089 47.883 2090 47.964 2091 48.185 2092 48.368 2093 48.52 2094 48.647 2095 48.753 2096 49.007 2097 49.217 2098 49.388 2099 49.529 2100 49.646