年份 | 美国 |
---|---|
2023 | - |
2022 | 6.36526 |
2021 | 6.33977 |
2020 | 6.3397 |
2019 | 6.35015 |
2018 | 6.35303 |
2017 | 6.36003 |
2016 | 6.37438 |
2015 | 6.38999 |
2014 | 6.42497 |
2013 | 6.49192 |
2012 | 6.58679 |
2011 | 6.71076 |
2010 | 6.84203 |
2009 | 6.94382 |
2008 | 6.99726 |
2007 | 7.00382 |
2006 | 6.979 |
2005 | 6.9384 |
2004 | 6.88801 |
2003 | 6.84505 |
2002 | 6.81593 |
2001 | 6.81158 |
2000 | 6.83403 |
1999 | 6.85748 |
1998 | 6.85602 |
1997 | 6.81359 |
1996 | 6.7306 |
1995 | 6.62678 |
1994 | 6.53537 |
1993 | 6.48383 |
1992 | 6.49871 |
1991 | 6.6359 |
1990 | 6.87113 |
1989 | 7.08916 |
1988 | 7.26666 |
1987 | 7.41849 |
1986 | 7.53119 |
1985 | 7.62751 |
1984 | 7.78851 |
1983 | 8.02326 |
1982 | 8.29795 |
1981 | 8.61163 |
1980 | 8.90623 |
1979 | 9.11511 |
1978 | 9.25982 |
1977 | 9.37193 |
1976 | 9.43879 |
1975 | 9.44993 |
1974 | 9.42528 |
1973 | 9.37292 |
1972 | 9.26755 |
1971 | 9.2962 |
1970 | 9.21986 |
1969 | 8.85476 |
1968 | 8.60001 |
1967 | 8.58451 |
1966 | 8.45678 |
1965 | 8.23193 |
1964 | 8.17985 |
1963 | 8.09118 |
1962 | 7.81776 |
1961 | 7.41642 |
1960 | 7.18607 |