年份 | 美国 |
---|---|
2023 | - |
2022 | - |
2021 | 0.611483 |
2020 | 0.187625 |
2019 | 0.368545 |
2018 | 0.319248 |
2017 | 0.162526 |
2016 | 0.0922955 |
2015 | 0.00752518 |
2014 | 0.292227 |
2013 | 0.30565 |
2012 | 0.205926 |
2011 | 0.370845 |
2010 | 0.293763 |
2009 | 0.25964 |
2008 | 0.521499 |
2007 | 0.356898 |
2006 | 0.349464 |
2005 | 0.350823 |
2004 | 0.283171 |
2003 | 0.211789 |
2002 | 0.172817 |
2001 | 0.169433 |
2000 | 0.307551 |
1999 | 0.164265 |
1998 | 0.0755585 |
1997 | 0.203604 |
1996 | 0.351312 |
1995 | 0.295557 |
1994 | 0.292003 |
1993 | 0.348054 |
1992 | 0.441873 |
1991 | 0.477259 |
1990 | 0.703237 |
1989 | 0.539634 |
1988 | 0.431204 |
1987 | 0.690239 |
1986 | 0.485561 |
1985 | 1.20811 |
1984 | 1.28028 |
1983 | 1.54216 |
1982 | 1.29087 |
1981 | 2.11596 |
1980 | 3.14542 |
1979 | 2.51516 |
1978 | 1.41342 |
1977 | 1.48213 |
1976 | 1.45989 |
1975 | 1.46934 |
1974 | 1.57099 |
1973 | 0.349942 |
1972 | 0.363639 |
1971 | 0.333819 |
1970 | 0.279989 |
1969 | - |
1968 | - |
1967 | - |
1966 | - |
1965 | - |
1964 | - |
1963 | - |
1962 | - |
1961 | - |
1960 | - |