Year Number 1950 71.604 1951 72.784 1952 74.106 1953 74.94 1954 75.101 1955 74.688 1956 76.087 1957 76.483 1958 76.314 1959 76.006 1960 75.734 1961 76.75 1962 77.687 1963 78.447 1964 78.808 1965 78.686 1966 79.99 1967 80.658 1968 80.855 1969 80.823 1970 80.706 1971 81.994 1972 82.941 1973 83.633 1974 84.112 1975 84.39 1976 86.13 1977 87.471 1978 88.486 1979 89.249 1980 89.801 1981 91.523 1982 92.886 1983 93.921 1984 94.624 1985 94.979 1986 97.078 1987 98.739 1988 100.031 1989 101.067 1990 101.918 1991 102.19 1992 102.172 1993 101.924 1994 101.46 1995 100.798 1996 100.896 1997 100.648 1998 100.185 1999 99.647 2000 99.103 2001 99.106 2002 98.963 2003 98.722 2004 98.423 2005 98.102 2006 98.66 2007 99.05 2008 99.291 2009 99.363 2010 99.243 2011 99.984 2012 100.358 2013 100.458 2014 100.387 2015 100.184 2016 99.826 2017 99.347 2018 98.695 2019 97.808 2020 96.685 2021 95.653 2022 94.439 2023 93.098 2024 91.712 2025 90.334 2026 89.229 2027 88.083 2028 86.933 2029 85.813 2030 84.739 2031 83.891 2032 83.045 2033 82.205 2034 81.365 2035 80.523 2036 79.818 2037 79.082 2038 78.314 2039 77.516 2040 76.691 2041 75.943 2042 75.153 2043 74.325 2044 73.462 2045 72.568 2046 71.736 2047 70.866 2048 69.968 2049 69.052 2050 68.129 2051 67.256 2052 66.378 2053 65.5 2054 64.632 2055 63.781 2056 63.008 2057 62.245 2058 61.497 2059 60.774 2060 60.081 2061 59.467 2062 58.872 2063 58.302 2064 57.763 2065 57.26 2066 56.828 2067 56.42 2068 56.04 2069 55.695 2070 55.389 2071 55.146 2072 54.928 2073 54.732 2074 54.553 2075 54.388 2076 54.249 2077 54.117 2078 53.991 2079 53.874 2080 53.768 2081 53.67 2082 53.574 2083 53.486 2084 53.416 2085 53.368 2086 53.327 2087 53.304 2088 53.302 2089 53.32 2090 53.36 2091 53.411 2092 53.474 2093 53.553 2094 53.66 2095 53.798 2096 53.933 2097 54.097 2098 54.292 2099 54.513 2100 54.754