Year Number 1950 49.145 1951 49.685 1952 50.142 1953 50.711 1954 51.302 1955 51.764 1956 52.007 1957 52.231 1958 52.358 1959 52.361 1960 52.278 1961 52.819 1962 53.041 1963 53.038 1964 52.925 1965 52.761 1966 53.061 1967 53.31 1968 53.528 1969 53.693 1970 53.775 1971 54.119 1972 54.317 1973 54.37 1974 54.254 1975 53.946 1976 53.673 1977 53.287 1978 52.728 1979 51.979 1980 51.098 1981 50.129 1982 49.085 1983 48.078 1984 47.223 1985 46.573 1986 46.337 1987 46.164 1988 46.07 1989 46.076 1990 46.194 1991 46.418 1992 46.765 1993 47.17 1994 47.522 1995 47.745 1996 48.166 1997 48.457 1998 48.615 1999 48.68 2000 48.674 2001 48.448 2002 48.17 2003 47.862 2004 47.553 2005 47.274 2006 47.031 2007 46.872 2008 46.805 2009 46.837 2010 46.977 2011 47.214 2012 47.515 2013 47.907 2014 48.37 2015 48.848 2016 49.429 2017 50.012 2018 50.611 2019 51.244 2020 51.935 2021 52.796 2022 53.693 2023 54.646 2024 55.689 2025 56.836 2026 57.994 2027 59.258 2028 60.59 2029 61.931 2030 63.248 2031 64.484 2032 65.69 2033 66.834 2034 67.87 2035 68.77 2036 69.417 2037 69.935 2038 70.36 2039 70.731 2040 71.081 2041 71.296 2042 71.51 2043 71.748 2044 72.057 2045 72.482 2046 72.887 2047 73.412 2048 74.036 2049 74.705 2050 75.374 2051 75.86 2052 76.353 2053 76.859 2054 77.376 2055 77.899 2056 78.24 2057 78.61 2058 78.986 2059 79.321 2060 79.59 2061 79.64 2062 79.678 2063 79.685 2064 79.657 2065 79.615 2066 79.393 2067 79.172 2068 78.973 2069 78.824 2070 78.733 2071 78.451 2072 78.239 2073 78.112 2074 78.067 2075 78.091 2076 77.937 2077 77.893 2078 77.941 2079 78.069 2080 78.292 2081 78.385 2082 78.583 2083 78.885 2084 79.271 2085 79.72 2086 79.966 2087 80.285 2088 80.661 2089 81.084 2090 81.555 2091 81.805 2092 82.1 2093 82.439 2094 82.821 2095 83.24 2096 83.397 2097 83.594 2098 83.831 2099 84.109 2100 84.433