Year Number 1950 59.398 1951 59.036 1952 58.005 1953 57.245 1954 57.122 1955 57.598 1956 58.823 1957 60.556 1958 62.659 1959 65.077 1960 67.965 1961 73.154 1962 79.113 1963 85.862 1964 92.963 1965 99.676 1966 102.428 1967 104.192 1968 104.911 1969 104.86 1970 104.351 1971 102.84 1972 101.343 1973 99.785 1974 97.919 1975 95.636 1976 93.907 1977 91.683 1978 89.247 1979 87.015 1980 85.196 1981 83.774 1982 82.857 1983 82.312 1984 81.898 1985 81.484 1986 81.702 1987 81.791 1988 81.771 1989 81.691 1990 81.548 1991 81.939 1992 82.009 1993 81.789 1994 81.278 1995 80.435 1996 78.929 1997 77.259 1998 75.384 1999 73.271 2000 70.948 2001 68.651 2002 66.287 2003 63.876 2004 61.501 2005 59.245 2006 57.112 2007 55.196 2008 53.528 2009 52.126 2010 51.001 2011 50.437 2012 49.987 2013 49.7 2014 49.598 2015 49.651 2016 49.903 2017 50.188 2018 50.483 2019 50.745 2020 50.935 2021 50.962 2022 50.978 2023 50.91 2024 50.695 2025 50.324 2026 49.949 2027 49.436 2028 48.818 2029 48.156 2030 47.495 2031 46.914 2032 46.346 2033 45.82 2034 45.362 2035 44.993 2036 44.832 2037 44.735 2038 44.709 2039 44.746 2040 44.836 2041 45.057 2042 45.308 2043 45.596 2044 45.924 2045 46.291 2046 46.767 2047 47.249 2048 47.746 2049 48.276 2050 48.846 2051 49.518 2052 50.21 2053 50.888 2054 51.505 2055 52.034 2056 52.566 2057 53.012 2058 53.364 2059 53.613 2060 53.761 2061 53.914 2062 53.967 2063 53.94 2064 53.851 2065 53.714 2066 53.643 2067 53.52 2068 53.39 2069 53.307 2070 53.307 2071 53.514 2072 53.78 2073 54.107 2074 54.501 2075 54.958 2076 55.616 2077 56.323 2078 57.047 2079 57.733 2080 58.345 2081 59.019 2082 59.618 2083 60.132 2084 60.553 2085 60.878 2086 61.249 2087 61.528 2088 61.722 2089 61.841 2090 61.898 2091 62.004 2092 62.051 2093 62.059 2094 62.053 2095 62.056 2096 62.154 2097 62.252 2098 62.361 2099 62.495 2100 62.657