| 时间 | 值 （美元） | 世界排名 |
|---|---|---|
| 2016 | 38894 | 22 |
| 2015 | 34474 | 28 |
| 2014 | 38096 | 29 |
| 2013 | 40454 | 30 |
| 2012 | 48603 | 18 |
| 2011 | 48168 | 22 |
| 2010 | 44508 | 21 |
| 2009 | 40855 | 24 |
| 2008 | 39339 | 33 |
| 2007 | 35275 | 34 |
| 2006 | 35434 | 31 |
| 2005 | 37218 | 23 |
| 2004 | 37689 | 18 |
| 2003 | 34808 | 15 |
| 2002 | 32289 | 11 |
| 2001 | 33846 | 9 |
| 2000 | 38532 | 6 |
| 1999 | 36027 | 8 |
| 1998 | 31903 | 10 |
| 1997 | 35022 | 7 |
| 1996 | 38437 | 6 |
| 1995 | 43440 | 5 |
| 1994 | 39269 | 5 |
| 1993 | 35866 | 5 |
| 1992 | 31376 | 6 |
| 1991 | 28874 | 6 |
| 1990 | 25417 | 12 |
| 1989 | 24792 | 7 |
| 1988 | 24880 | 5 |
| 1987 | 20594 | 11 |
| 1986 | 17080 | 11 |