| 时期 |
美国 （亿美元） |
|---|---|
| 2021 | |
| 2020 | |
| 2019 | |
| 2018 | |
| 2017 | |
| 2016 | |
| 2015 | |
| 2014 | |
| 2013 | |
| 2012 | |
| 2011 | 157738.15 |
| 2010 | 152020.15 |
| 2009 | 146847.01 |
| 2008 | 149305.57 |
| 2007 | 146109.06 |
| 2006 | 142725.64 |
| 2005 | 136465.81 |
| 2004 | 127401.92 |
| 2003 | 115331.29 |
| 2002 | 107301.51 |
| 2001 | 104593.35 |
| 2000 | 101465.84 |
| 1999 | 93977.91 |
| 1998 | 88357.69 |
| 1997 | 85269.98 |
| 1996 | 81543.21 |
| 1995 | 77319.70 |
| 1994 | 72767.17 |
| 1993 | 68584.27 |
| 1992 | 65870.44 |
| 1991 | 61406.56 |
| 1990 | 60062.24 |
| 1989 | 58662.94 |
| 1988 | 57441.06 |
| 1987 | 51833.58 |
| 1986 | 45881.18 |
| 1985 | 41547.14 |
| 1984 | 38216.73 |
| 1983 | 34057.05 |
| 1982 | 32937.08 |
| 1981 | 32958.01 |
| 1980 | 30413.82 |
| 1979 | 27456.55 |
| 1978 | 23956.00 |
| 1977 | 21128.45 |
| 1976 | 19540.16 |
| 1975 | 18376.16 |
| 1974 | 17075.01 |
| 1973 | 15446.68 |
| 1972 | 13175.47 |
| 1971 | 11677.26 |
| 1970 | 10729.02 |
| 1969 | 10279.90 |
| 1968 | 9520.34 |
| 1967 | 8682.95 |
| 1966 | 8241.84 |
| 1965 | 7532.95 |
| 1964 | 6923.28 |
| 1963 | 6462.34 |
| 1962 | 6121.79 |