Year Number 1950 53.863 1951 53.369 1952 52.327 1953 51.446 1954 51.164 1955 51.591 1956 52.498 1957 54.037 1958 55.931 1959 57.768 1960 59.287 1961 60.879 1962 61.98 1963 62.684 1964 63.182 1965 63.55 1966 63.531 1967 63.347 1968 62.933 1969 62.24 1970 61.288 1971 59.833 1972 58.529 1973 57.344 1974 56.214 1975 55.102 1976 54.292 1977 53.314 1978 52.277 1979 51.345 1980 50.602 1981 49.939 1982 49.442 1983 49.111 1984 48.898 1985 48.786 1986 49.13 1987 49.462 1988 49.776 1989 50.117 1990 50.497 1991 51.017 1992 51.489 1993 51.825 1994 51.905 1995 51.668 1996 50.976 1997 50.117 1998 49.107 1999 48.024 2000 46.949 2001 46.288 2002 45.678 2003 45.059 2004 44.351 2005 43.52 2006 42.886 2007 42.089 2008 41.296 2009 40.715 2010 40.456 2011 40.667 2012 41.12 2013 41.72 2014 42.345 2015 42.957 2016 44.175 2017 45.297 2018 46.372 2019 47.478 2020 48.632 2021 49.783 2022 51.043 2023 52.284 2024 53.33 2025 54.102 2026 55.026 2027 55.654 2028 56.004 2029 56.137 2030 56.086 2031 56.012 2032 55.795 2033 55.491 2034 55.165 2035 54.879 2036 54.859 2037 54.896 2038 54.983 2039 55.107 2040 55.264 2041 55.691 2042 56.129 2043 56.612 2044 57.176 2045 57.831 2046 58.81 2047 59.838 2048 60.91 2049 62.021 2050 63.156 2051 64.549 2052 65.955 2053 67.278 2054 68.382 2055 69.173 2056 69.879 2057 70.318 2058 70.442 2059 70.212 2060 69.636 2061 68.938 2062 67.937 2063 66.754 2064 65.549 2065 64.417 2066 63.523 2067 62.724 2068 62.017 2069 61.386 2070 60.835 2071 60.551 2072 60.351 2073 60.266 2074 60.337 2075 60.576 2076 61.147 2077 61.881 2078 62.711 2079 63.524 2080 64.233 2081 65.003 2082 65.697 2083 66.301 2084 66.811 2085 67.228 2086 67.667 2087 68.038 2088 68.314 2089 68.48 2090 68.541 2091 68.537 2092 68.441 2093 68.278 2094 68.079 2095 67.862 2096 67.577 2097 67.299 2098 67.047 2099 66.837 2100 66.683