Year Number 1950 75.029 1951 76.307 1952 77.543 1953 78.605 1954 79.408 1955 79.943 1956 81.071 1957 81.797 1958 82.261 1959 82.614 1960 82.92 1961 83.688 1962 84.346 1963 84.887 1964 85.272 1965 85.491 1966 86.19 1967 86.65 1968 86.956 1969 87.243 1970 87.588 1971 88.389 1972 89.25 1973 90.109 1974 90.846 1975 91.392 1976 93.674 1977 95.656 1978 97.379 1979 98.914 1980 100.259 1981 101.134 1982 101.715 1983 102.007 1984 102.05 1985 101.906 1986 99.031 1987 96.266 1988 93.639 1989 91.118 1990 88.689 1991 87.736 1992 86.651 1993 85.49 1994 84.314 1995 83.142 1996 82.332 1997 81.377 1998 80.314 1999 79.141 2000 77.835 2001 77.716 2002 77.5 2003 77.132 2004 76.584 2005 75.873 2006 74.897 2007 73.859 2008 72.803 2009 71.826 2010 71.006 2011 69.969 2012 69.128 2013 68.448 2014 67.846 2015 67.267 2016 67.093 2017 66.759 2018 66.363 2019 66.022 2020 65.763 2021 65.405 2022 65.175 2023 64.959 2024 64.604 2025 64.049 2026 63.465 2027 62.711 2028 61.841 2029 60.954 2030 60.106 2031 59.355 2032 58.621 2033 57.914 2034 57.233 2035 56.582 2036 56.034 2037 55.511 2038 55.017 2039 54.554 2040 54.123 2041 53.78 2042 53.458 2043 53.155 2044 52.867 2045 52.591 2046 52.373 2047 52.156 2048 51.951 2049 51.771 2050 51.623 2051 51.536 2052 51.463 2053 51.406 2054 51.373 2055 51.366 2056 51.401 2057 51.452 2058 51.508 2059 51.552 2060 51.578 2061 51.605 2062 51.608 2063 51.591 2064 51.557 2065 51.51 2066 51.456 2067 51.387 2068 51.314 2069 51.247 2070 51.194 2071 51.16 2072 51.129 2073 51.125 2074 51.178 2075 51.306 2076 51.508 2077 51.768 2078 52.072 2079 52.396 2080 52.725 2081 53.061 2082 53.394 2083 53.726 2084 54.057 2085 54.388 2086 54.714 2087 55.03 2088 55.339 2089 55.644 2090 55.945 2091 56.232 2092 56.512 2093 56.79 2094 57.07 2095 57.355 2096 57.623 2097 57.892 2098 58.166 2099 58.451 2100 58.752