Year Number 1950 56.46 1951 57.712 1952 59.614 1953 61.645 1954 63.703 1955 65.891 1956 69.213 1957 72.216 1958 75.157 1959 78.203 1960 81.346 1961 84.512 1962 87.65 1963 90.585 1964 93.036 1965 94.854 1966 96.307 1967 97.169 1968 97.458 1969 97.275 1970 96.717 1971 95.981 1972 94.93 1973 93.644 1974 92.187 1975 90.612 1976 89.888 1977 88.954 1978 87.9 1979 86.844 1980 85.849 1981 84.61 1982 83.51 1983 82.496 1984 81.478 1985 80.425 1986 79.572 1987 78.626 1988 77.636 1989 76.674 1990 75.761 1991 74.976 1992 74.19 1993 73.338 1994 72.283 1995 70.939 1996 69.591 1997 67.79 1998 65.698 1999 63.558 2000 61.501 2001 58.976 2002 56.864 2003 54.957 2004 52.994 2005 50.916 2006 49.281 2007 47.511 2008 45.782 2009 44.345 2010 43.31 2011 42.68 2012 42.32 2013 42.22 2014 42.305 2015 42.511 2016 42.839 2017 43.276 2018 43.78 2019 44.306 2020 44.827 2021 45.306 2022 45.782 2023 46.23 2024 46.632 2025 46.982 2026 47.287 2027 47.549 2028 47.774 2029 47.985 2030 48.205 2031 48.426 2032 48.664 2033 48.936 2034 49.262 2035 49.658 2036 50.111 2037 50.63 2038 51.214 2039 51.86 2040 52.568 2041 53.291 2042 54.059 2043 54.886 2044 55.783 2045 56.748 2046 57.701 2047 58.709 2048 59.77 2049 60.877 2050 62.027 2051 63.128 2052 64.256 2053 65.41 2054 66.59 2055 67.796 2056 68.927 2057 70.088 2058 71.201 2059 72.145 2060 72.848 2061 73.195 2062 73.313 2063 73.272 2064 73.175 2065 73.089 2066 72.876 2067 72.681 2068 72.532 2069 72.456 2070 72.482 2071 72.47 2072 72.577 2073 72.8 2074 73.126 2075 73.54 2076 73.89 2077 74.338 2078 74.862 2079 75.427 2080 76.007 2081 76.44 2082 76.896 2083 77.371 2084 77.838 2085 78.272 2086 78.514 2087 78.768 2088 78.992 2089 79.171 2090 79.333 2091 79.329 2092 79.296 2093 79.277 2094 79.316 2095 79.418 2096 79.301 2097 79.266 2098 79.305 2099 79.397 2100 79.526