Year Number 1950 68.779 1951 68.599 1952 68.83 1953 69.123 1954 68.967 1955 68.221 1956 68.14 1957 67.308 1958 66.265 1959 65.673 1960 65.871 1961 65.981 1962 67.445 1963 69.612 1964 71.494 1965 72.614 1966 74.818 1967 75.551 1968 75.529 1969 75.806 1970 76.8 1971 76.974 1972 78.076 1973 79.433 1974 79.943 1975 79.08 1976 77.732 1977 75.008 1978 71.477 1979 68.036 1980 65.128 1981 61.92 1982 59.551 1983 57.691 1984 55.862 1985 53.914 1986 52.463 1987 50.807 1988 49.19 1989 47.923 1990 47.098 1991 46.708 1992 46.477 1993 46.416 1994 46.469 1995 46.575 1996 46.376 1997 46.434 1998 46.566 1999 46.561 2000 46.338 2001 46.047 2002 45.51 2003 44.843 2004 44.244 2005 43.811 2006 43.453 2007 43.251 2008 43.174 2009 43.149 2010 43.144 2011 43.081 2012 43.059 2013 43.092 2014 43.208 2015 43.427 2016 43.756 2017 44.187 2018 44.687 2019 45.2 2020 45.694 2021 46.056 2022 46.407 2023 46.848 2024 47.533 2025 48.565 2026 49.905 2027 51.584 2028 53.528 2029 55.601 2030 57.705 2031 59.753 2032 61.809 2033 63.888 2034 66.032 2035 68.26 2036 70.425 2037 72.67 2038 74.856 2039 76.767 2040 78.266 2041 79.177 2042 79.648 2043 79.843 2044 79.994 2045 80.238 2046 80.327 2047 80.515 2048 80.807 2049 81.257 2050 81.943 2051 82.643 2052 83.577 2053 84.73 2054 85.948 2055 87.046 2056 87.715 2057 88.34 2058 88.867 2059 89.314 2060 89.766 2061 90.044 2062 90.328 2063 90.672 2064 91.078 2065 91.498 2066 91.694 2067 91.985 2068 92.276 2069 92.532 2070 92.813 2071 92.887 2072 92.922 2073 93.032 2074 93.305 2075 93.711 2076 93.795 2077 94.013 2078 94.342 2079 94.713 2080 95.068 2081 95.099 2082 95.227 2083 95.367 2084 95.482 2085 95.623 2086 95.512 2087 95.422 2088 95.411 2089 95.513 2090 95.699 2091 95.548 2092 95.496 2093 95.516 2094 95.59 2095 95.723 2096 95.531 2097 95.432 2098 95.443 2099 95.546 2100 95.701