Year Number 1950 52.7 1951 52.95 1952 53.042 1953 53.237 1954 53.511 1955 53.772 1956 53.952 1957 54.231 1958 54.532 1959 54.771 1960 54.894 1961 54.743 1962 54.589 1963 54.379 1964 54.076 1965 53.683 1966 53.489 1967 52.961 1968 52.295 1969 51.754 1970 51.473 1971 51.529 1972 51.89 1973 52.415 1974 52.879 1975 53.166 1976 53.52 1977 53.704 1978 53.737 1979 53.606 1980 53.29 1981 52.618 1982 51.538 1983 50.207 1984 48.891 1985 47.769 1986 47.148 1987 46.811 1988 46.593 1989 46.262 1990 45.71 1991 45.586 1992 45.243 1993 44.763 1994 44.288 1995 43.911 1996 43.536 1997 43.294 1998 43.129 1999 42.94 2000 42.68 2001 42.517 2002 42.262 2003 41.998 2004 41.848 2005 41.88 2006 42.046 2007 42.43 2008 42.968 2009 43.544 2010 44.11 2011 44.987 2012 45.766 2013 46.545 2014 47.495 2015 48.705 2016 50.069 2017 51.703 2018 53.48 2019 55.212 2020 56.775 2021 58.119 2022 59.341 2023 60.44 2024 61.44 2025 62.359 2026 63.225 2027 63.994 2028 64.699 2029 65.406 2030 66.165 2031 66.897 2032 67.717 2033 68.602 2034 69.486 2035 70.331 2036 71.045 2037 71.744 2038 72.478 2039 73.354 2040 74.456 2041 75.646 2042 77.03 2043 78.595 2044 80.25 2045 81.889 2046 83.312 2047 84.744 2048 86.128 2049 87.411 2050 88.582 2051 89.489 2052 90.297 2053 90.965 2054 91.431 2055 91.649 2056 91.406 2057 90.96 2058 90.356 2059 89.658 2060 88.909 2061 87.913 2062 86.956 2063 86.017 2064 85.081 2065 84.169 2066 83.099 2067 82.094 2068 81.231 2069 80.575 2070 80.131 2071 79.669 2072 79.477 2073 79.501 2074 79.674 2075 79.973 2076 80.243 2077 80.68 2078 81.249 2079 81.884 2080 82.529 2081 82.976 2082 83.452 2083 83.926 2084 84.389 2085 84.845 2086 85.054 2087 85.255 2088 85.455 2089 85.653 2090 85.832 2091 85.692 2092 85.565 2093 85.45 2094 85.355 2095 85.296 2096 84.969 2097 84.701 2098 84.521 2099 84.454 2100 84.508