年份 | 美国 |
---|---|
2023 | - |
2022 | - |
2021 | 17.2439 |
2020 | 17.2439 |
2019 | 17.2439 |
2018 | 17.2439 |
2017 | 17.2439 |
2016 | 17.1842 |
2015 | 17.1245 |
2014 | 17.0648 |
2013 | 17.0052 |
2012 | 16.9455 |
2011 | 17.0936 |
2010 | 17.2416 |
2009 | 17.3897 |
2008 | 17.5378 |
2007 | 17.6579 |
2006 | 17.9029 |
2005 | 18.148 |
2004 | 18.3931 |
2003 | 18.6349 |
2002 | 18.88 |
2001 | 19.1445 |
2000 | 19.141 |
1999 | 19.1472 |
1998 | 19.3015 |
1997 | 19.39 |
1996 | 19.5444 |
1995 | 19.8537 |
1994 | 19.8646 |
1993 | 19.9529 |
1992 | 20.0984 |
1991 | 20.2726 |
1990 | 20.2726 |
1989 | 20.2781 |
1988 | 20.2798 |
1987 | 20.2798 |
1986 | 20.5007 |
1985 | 20.5007 |
1984 | 20.5007 |
1983 | 20.5007 |
1982 | 20.5007 |
1981 | 20.6088 |
1980 | 20.6088 |
1979 | 20.6088 |
1978 | 20.6088 |
1977 | 20.3683 |
1976 | 20.3595 |
1975 | 20.3595 |
1974 | 20.3595 |
1973 | 20.4226 |
1972 | 20.4767 |
1971 | 20.5416 |
1970 | 20.6066 |
1969 | 20.6622 |
1968 | 19.7621 |
1967 | 19.051 |
1966 | 19.1839 |
1965 | 19.3253 |
1964 | 19.4308 |
1963 | 19.6064 |
1962 | 19.3357 |
1961 | 19.7217 |
1960 | - |