Year Number 1950 75.736 1951 75.742 1952 75.812 1953 75.539 1954 74.875 1955 73.982 1956 74.719 1957 74.891 1958 74.818 1959 74.683 1960 74.485 1961 73.804 1962 73.372 1963 72.92 1964 72.109 1965 70.839 1966 69.636 1967 68.104 1968 66.388 1969 64.713 1970 63.192 1971 62.176 1972 61.121 1973 60.188 1974 59.513 1975 59.116 1976 58.421 1977 58.089 1978 57.876 1979 57.445 1980 56.642 1981 55.631 1982 54.358 1983 52.988 1984 51.77 1985 50.834 1986 50.46 1987 50.228 1988 50.128 1989 50.115 1990 50.139 1991 50.11 1992 50.085 1993 49.974 1994 49.687 1995 49.218 1996 48.891 1997 48.34 1998 47.683 1999 47.063 2000 46.538 2001 46.006 2002 45.614 2003 45.293 2004 44.918 2005 44.429 2006 43.968 2007 43.371 2008 42.714 2009 42.122 2010 41.671 2011 41.316 2012 41.122 2013 41.085 2014 41.181 2015 41.395 2016 41.964 2017 42.578 2018 43.241 2019 43.973 2020 44.756 2021 45.574 2022 46.436 2023 47.314 2024 48.146 2025 48.899 2026 49.628 2027 50.263 2028 50.831 2029 51.384 2030 51.955 2031 52.576 2032 53.204 2033 53.821 2034 54.398 2035 54.922 2036 55.438 2037 55.904 2038 56.347 2039 56.807 2040 57.315 2041 57.903 2042 58.521 2043 59.193 2044 59.944 2045 60.78 2046 61.746 2047 62.808 2048 63.928 2049 65.042 2050 66.109 2051 67.181 2052 68.193 2053 69.167 2054 70.139 2055 71.128 2056 72.112 2057 73.101 2058 74.068 2059 74.961 2060 75.742 2061 76.374 2062 76.909 2063 77.347 2064 77.708 2065 78.006 2066 78.201 2067 78.357 2068 78.462 2069 78.487 2070 78.417 2071 78.192 2072 77.904 2073 77.604 2074 77.355 2075 77.191 2076 77.046 2077 77.034 2078 77.124 2079 77.267 2080 77.443 2081 77.601 2082 77.829 2083 78.125 2084 78.47 2085 78.84 2086 79.121 2087 79.463 2088 79.84 2089 80.223 2090 80.601 2091 80.838 2092 81.101 2093 81.382 2094 81.668 2095 81.946 2096 82.028 2097 82.141 2098 82.273 2099 82.411 2100 82.558