Year Number 1950 73.335 1951 74.994 1952 76.579 1953 77.799 1954 78.757 1955 79.542 1956 81.188 1957 82.731 1958 84.09 1959 85.062 1960 85.505 1961 85.798 1962 85.418 1963 84.749 1964 84.132 1965 83.638 1966 82.928 1967 82.796 1968 82.87 1969 82.565 1970 81.573 1971 80.725 1972 79.009 1973 76.751 1974 74.5 1975 72.492 1976 69.194 1977 66.229 1978 63.528 1979 61.053 1980 58.873 1981 56.939 1982 55.467 1983 54.228 1984 53.099 1985 52.08 1986 51.863 1987 51.963 1988 52.274 1989 52.725 1990 53.274 1991 53.571 1992 53.917 1993 54.246 1994 54.541 1995 54.793 1996 54.707 1997 54.658 1998 54.523 1999 54.35 2000 54.261 2001 52.766 2002 51.762 2003 51.01 2004 50.319 2005 49.735 2006 49.563 2007 49.267 2008 48.997 2009 48.996 2010 49.346 2011 48.978 2012 49.167 2013 49.74 2014 50.423 2015 51.097 2016 52.093 2017 52.934 2018 53.754 2019 54.773 2020 56.09 2021 57.221 2022 58.673 2023 60.326 2024 61.967 2025 63.478 2026 64.748 2027 65.891 2028 66.906 2029 67.863 2030 68.786 2031 69.387 2032 69.933 2033 70.42 2034 70.841 2035 71.185 2036 71.206 2037 71.191 2038 71.129 2039 71 2040 70.795 2041 70.272 2042 69.714 2043 69.163 2044 68.692 2045 68.333 2046 67.854 2047 67.509 2048 67.291 2049 67.191 2050 67.192 2051 67.063 2052 67.051 2053 67.164 2054 67.417 2055 67.81 2056 68.117 2057 68.596 2058 69.169 2059 69.74 2060 70.254 2061 70.494 2062 70.696 2063 70.881 2064 71.101 2065 71.366 2066 71.432 2067 71.568 2068 71.748 2069 71.928 2070 72.099 2071 71.997 2072 71.892 2073 71.851 2074 71.957 2075 72.242 2076 72.382 2077 72.712 2078 73.187 2079 73.743 2080 74.324 2081 74.644 2082 75.018 2083 75.454 2084 75.952 2085 76.497 2086 76.775 2087 77.134 2088 77.538 2089 77.963 2090 78.407 2091 78.593 2092 78.805 2093 79.066 2094 79.381 2095 79.744 2096 79.808 2097 79.937 2098 80.135 2099 80.374 2100 80.662