Year Number 1950 58.615 1951 58.27 1952 57.475 1953 56.634 1954 56.05 1955 55.823 1956 56.549 1957 57.253 1958 58.132 1959 59.236 1960 60.498 1961 61.802 1962 63.074 1963 64.2 1964 65.019 1965 65.457 1966 65.791 1967 65.672 1968 65.143 1969 64.388 1970 63.548 1971 62.21 1972 61.22 1973 60.422 1974 59.548 1975 58.452 1976 57.704 1977 56.7 1978 55.532 1979 54.433 1980 53.538 1981 52.765 1982 52.165 1983 51.734 1984 51.41 1985 51.159 1986 51.089 1987 51.058 1988 51.076 1989 51.194 1990 51.431 1991 52.135 1992 52.931 1993 53.739 1994 54.396 1995 54.77 1996 54.728 1997 54.387 1998 53.811 1999 53.146 2000 52.485 2001 51.994 2002 51.602 2003 51.126 2004 50.333 2005 49.143 2006 48.507 2007 47.564 2008 46.579 2009 45.844 2010 45.446 2011 45.544 2012 45.612 2013 45.629 2014 45.621 2015 45.673 2016 46.418 2017 47.304 2018 48.332 2019 49.44 2020 50.541 2021 51.468 2022 52.504 2023 53.518 2024 54.361 2025 54.997 2026 55.766 2027 56.276 2028 56.591 2029 56.817 2030 56.991 2031 57.13 2032 57.228 2033 57.304 2034 57.37 2035 57.462 2036 57.611 2037 57.826 2038 58.118 2039 58.504 2040 58.997 2041 59.645 2042 60.397 2043 61.252 2044 62.197 2045 63.216 2046 64.356 2047 65.522 2048 66.751 2049 68.094 2050 69.57 2051 71.133 2052 72.819 2053 74.549 2054 76.195 2055 77.66 2056 78.908 2057 79.995 2058 80.861 2059 81.465 2060 81.792 2061 81.823 2062 81.615 2063 81.161 2064 80.456 2065 79.508 2066 78.272 2067 76.856 2068 75.408 2069 74.124 2070 73.129 2071 72.371 2072 71.917 2073 71.764 2074 71.902 2075 72.324 2076 73.006 2077 74.015 2078 75.262 2079 76.569 2080 77.79 2081 78.86 2082 79.865 2083 80.783 2084 81.619 2085 82.383 2086 82.991 2087 83.55 2088 84.034 2089 84.42 2090 84.696 2091 84.725 2092 84.699 2093 84.597 2094 84.429 2095 84.219 2096 83.748 2097 83.235 2098 82.727 2099 82.31 2100 82.024