年份 | 美国 |
---|---|
2023 | - |
2022 | 6.3644 |
2021 | 6.34984 |
2020 | 6.33873 |
2019 | 6.35804 |
2018 | 6.42572 |
2017 | 6.52511 |
2016 | 6.65225 |
2015 | 6.78527 |
2014 | 6.88661 |
2013 | 6.92849 |
2012 | 6.90754 |
2011 | 6.83837 |
2010 | 6.76055 |
2009 | 6.71034 |
2008 | 6.6943 |
2007 | 6.7 |
2006 | 6.73067 |
2005 | 6.78513 |
2004 | 6.83696 |
2003 | 6.85445 |
2002 | 6.81978 |
2001 | 6.72265 |
2000 | 6.58996 |
1999 | 6.48424 |
1998 | 6.4273 |
1997 | 6.42309 |
1996 | 6.52077 |
1995 | 6.72325 |
1994 | 6.9428 |
1993 | 7.13402 |
1992 | 7.29184 |
1991 | 7.39753 |
1990 | 7.48982 |
1989 | 7.65244 |
1988 | 7.8841 |
1987 | 8.14309 |
1986 | 8.4159 |
1985 | 8.67137 |
1984 | 8.85074 |
1983 | 8.97449 |
1982 | 9.07926 |
1981 | 9.1284 |
1980 | 9.12525 |
1979 | 9.10365 |
1978 | 9.05608 |
1977 | 8.95906 |
1976 | 8.97472 |
1975 | 8.88779 |
1974 | 8.54379 |
1973 | 8.30613 |
1972 | 8.29219 |
1971 | 8.16869 |
1970 | 7.95399 |
1969 | 7.90625 |
1968 | 7.81796 |
1967 | 7.53832 |
1966 | 7.13611 |
1965 | 6.894 |
1964 | 6.78302 |
1963 | 6.58873 |
1962 | 6.34674 |
1961 | 6.22156 |
1960 | 6.17375 |