Year Number 1950 57.489 1951 56.588 1952 55.509 1953 54.368 1954 53.295 1955 52.366 1956 51.304 1957 50.424 1958 49.739 1959 49.222 1960 48.847 1961 49.111 1962 49.287 1963 49.418 1964 49.552 1965 49.711 1966 49.915 1967 50.119 1968 50.306 1969 50.475 1970 50.643 1971 50.887 1972 51.108 1973 51.252 1974 51.242 1975 51.061 1976 51.332 1977 51.308 1978 51.058 1979 50.697 1980 50.301 1981 49.915 1982 49.644 1983 49.473 1984 49.356 1985 49.288 1986 49.615 1987 49.865 1988 50.009 1989 50.027 1990 49.88 1991 50.801 1992 51.517 1993 52.004 1994 52.277 1995 52.348 1996 51.836 1997 51.223 1998 50.548 1999 49.809 2000 49.01 2001 48.4 2002 47.921 2003 47.528 2004 47.187 2005 46.891 2006 47.14 2007 47.307 2008 47.48 2009 47.764 2010 48.207 2011 48.915 2012 49.654 2013 50.427 2014 51.259 2015 52.184 2016 52.698 2017 53.472 2018 54.334 2019 55.064 2020 55.555 2021 56.379 2022 56.854 2023 57.117 2024 57.412 2025 57.861 2026 58.515 2027 59.33 2028 60.19 2029 60.867 2030 61.231 2031 61.512 2032 61.543 2033 61.41 2034 61.27 2035 61.224 2036 61.45 2037 61.789 2038 62.178 2039 62.523 2040 62.786 2041 63.178 2042 63.49 2043 63.782 2044 64.12 2045 64.532 2046 65.108 2047 65.738 2048 66.437 2049 67.229 2050 68.129 2051 69.262 2052 70.503 2053 71.777 2054 72.966 2055 73.978 2056 74.944 2057 75.789 2058 76.387 2059 76.578 2060 76.291 2061 75.645 2062 74.557 2063 73.234 2064 71.958 2065 70.883 2066 70.014 2067 69.355 2068 68.88 2069 68.56 2070 68.387 2071 68.451 2072 68.717 2073 69.098 2074 69.453 2075 69.69 2076 69.866 2077 69.925 2078 69.938 2079 70.006 2080 70.171 2081 70.46 2082 70.871 2083 71.357 2084 71.835 2085 72.253 2086 72.672 2087 73.105 2088 73.494 2089 73.81 2090 74.062 2091 74.207 2092 74.266 2093 74.278 2094 74.287 2095 74.294 2096 74.083 2097 73.904 2098 73.768 2099 73.66 2100 73.569