年份 | 美国 |
---|---|
2023 | - |
2022 | 6.20558 |
2021 | 6.21776 |
2020 | 6.1931 |
2019 | 6.14587 |
2018 | 6.07481 |
2017 | 5.96604 |
2016 | 5.94021 |
2015 | 5.84095 |
2014 | 5.58507 |
2013 | 5.4109 |
2012 | 5.3453 |
2011 | 5.21348 |
2010 | 5.04934 |
2009 | 4.94135 |
2008 | 4.80651 |
2007 | 4.63502 |
2006 | 4.38114 |
2005 | 4.20469 |
2004 | 4.14155 |
2003 | 4.02862 |
2002 | 3.89549 |
2001 | 3.85977 |
2000 | 3.83431 |
1999 | 3.76068 |
1998 | 3.75255 |
1997 | 3.78875 |
1996 | 3.83331 |
1995 | 3.94391 |
1994 | 4.16235 |
1993 | 4.32149 |
1992 | 4.41183 |
1991 | 4.48612 |
1990 | 4.43885 |
1989 | 4.28135 |
1988 | 4.24088 |
1987 | 4.28189 |
1986 | 4.24084 |
1985 | 4.28417 |
1984 | 4.41762 |
1983 | 4.38249 |
1982 | 4.26069 |
1981 | 4.24787 |
1980 | 4.19689 |
1979 | 4.07454 |
1978 | 4.02054 |
1977 | 4.07717 |
1976 | 4.13111 |
1975 | 4.16429 |
1974 | 4.1815 |
1973 | 4.18065 |
1972 | 4.16433 |
1971 | 4.09904 |
1970 | 4.04414 |
1969 | 4.01091 |
1968 | 3.91162 |
1967 | 3.82905 |
1966 | 3.78381 |
1965 | 3.71056 |
1964 | 3.67396 |
1963 | 3.74185 |
1962 | 3.78988 |
1961 | 3.80251 |
1960 | 3.87152 |