Year Number 1950 68.061 1951 68.271 1952 67.75 1953 67.61 1954 68.191 1955 69.374 1956 69.877 1957 71.151 1958 72.653 1959 73.799 1960 74.249 1961 74.498 1962 73.916 1963 72.547 1964 70.779 1965 68.983 1966 69.031 1967 69.13 1968 69.266 1969 69.411 1970 69.591 1971 67.089 1972 64.705 1973 62.721 1974 61.155 1975 59.834 1976 58.282 1977 56.711 1978 55.187 1979 53.719 1980 52.303 1981 52.589 1982 52.764 1983 52.923 1984 53.115 1985 53.317 1986 53.653 1987 53.8 1988 54.007 1989 54.368 1990 54.791 1991 54.51 1992 54.173 1993 53.802 1994 53.322 1995 52.693 1996 52.274 1997 51.468 1998 50.468 1999 49.436 2000 48.431 2001 47.453 2002 46.539 2003 45.741 2004 45.002 2005 44.252 2006 43.709 2007 43.115 2008 42.521 2009 41.976 2010 41.516 2011 41.432 2012 41.363 2013 41.363 2014 41.456 2015 41.636 2016 41.986 2017 42.379 2018 42.828 2019 43.317 2020 43.825 2021 44.404 2022 45 2023 45.6 2024 46.177 2025 46.711 2026 47.273 2027 47.762 2028 48.211 2029 48.644 2030 49.07 2031 49.511 2032 49.917 2033 50.322 2034 50.747 2035 51.199 2036 51.676 2037 52.175 2038 52.724 2039 53.333 2040 54.006 2041 54.739 2042 55.509 2043 56.364 2044 57.348 2045 58.479 2046 59.736 2047 61.123 2048 62.6 2049 64.059 2050 65.416 2051 66.624 2052 67.702 2053 68.719 2054 69.768 2055 70.901 2056 72.031 2057 73.221 2058 74.439 2059 75.601 2060 76.641 2061 77.459 2062 78.155 2063 78.75 2064 79.255 2065 79.672 2066 79.849 2067 79.929 2068 79.964 2069 80.005 2070 80.079 2071 80.02 2072 79.997 2073 80.047 2074 80.16 2075 80.306 2076 80.334 2077 80.449 2078 80.614 2079 80.79 2080 80.982 2081 81.052 2082 81.122 2083 81.254 2084 81.459 2085 81.708 2086 81.791 2087 81.943 2088 82.14 2089 82.353 2090 82.585 2091 82.671 2092 82.784 2093 82.943 2094 83.148 2095 83.389 2096 83.442 2097 83.517 2098 83.625 2099 83.78 2100 83.996