Year Number 1950 77.846 1951 77.3 1952 75.397 1953 73.062 1954 71.03 1955 69.661 1956 68.936 1957 68.927 1958 69.395 1959 69.87 1960 69.909 1961 72.453 1962 73.69 1963 73.725 1964 73.175 1965 72.659 1966 72.988 1967 73.505 1968 74.344 1969 75.3 1970 76.227 1971 79.588 1972 81.803 1973 83.066 1974 83.778 1975 84.275 1976 86.101 1977 88.077 1978 90.044 1979 91.583 1980 92.509 1981 95.13 1982 96.421 1983 96.844 1984 97.002 1985 97.223 1986 97.159 1987 97.017 1988 96.832 1989 96.39 1990 95.526 1991 96.899 1992 97.741 1993 98.023 1994 97.844 1995 97.337 1996 97.368 1997 96.951 1998 96.233 1999 95.382 2000 94.548 2001 94.852 2002 94.96 2003 94.964 2004 94.924 2005 94.861 2006 95.354 2007 95.701 2008 95.873 2009 95.839 2010 95.618 2011 95.687 2012 95.546 2013 95.228 2014 94.759 2015 94.168 2016 94.025 2017 93.603 2018 92.978 2019 92.249 2020 91.469 2021 90.9 2022 90.267 2023 89.535 2024 88.652 2025 87.617 2026 86.859 2027 85.905 2028 84.827 2029 83.716 2030 82.627 2031 81.833 2032 80.998 2033 80.113 2034 79.154 2035 78.121 2036 77.294 2037 76.362 2038 75.367 2039 74.357 2040 73.362 2041 72.598 2042 71.795 2043 70.954 2044 70.072 2045 69.155 2046 68.413 2047 67.606 2048 66.746 2049 65.848 2050 64.926 2051 64.16 2052 63.348 2053 62.504 2054 61.643 2055 60.778 2056 60.075 2057 59.344 2058 58.599 2059 57.856 2060 57.127 2061 56.561 2062 55.981 2063 55.398 2064 54.821 2065 54.26 2066 53.844 2067 53.422 2068 53 2069 52.581 2070 52.171 2071 51.896 2072 51.605 2073 51.308 2074 51.02 2075 50.751 2076 50.604 2077 50.45 2078 50.29 2079 50.124 2080 49.956 2081 49.883 2082 49.788 2083 49.678 2084 49.563 2085 49.45 2086 49.433 2087 49.395 2088 49.344 2089 49.289 2090 49.239 2091 49.282 2092 49.308 2093 49.325 2094 49.337 2095 49.351 2096 49.466 2097 49.561 2098 49.644 2099 49.722 2100 49.804