| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 49.7 | 33 |
| 2015 | 49.5 | 35 |
| 2014 | 55.3 | 35 |
| 2013 | 56.6 | 35 |
| 2012 | 59.1 | 32 |
| 2011 | 71.3 | 26 |
| 2010 | 81.6 | 23 |
| 2009 | 106.4 | 21 |
| 2008 | 105.7 | 21 |
| 2007 | 85.3 | 21 |
| 2006 | 76.1 | 20 |
| 2005 | 70.3 | 19 |
| 2004 | 62.7 | 20 |
| 2003 | 50.4 | 21 |
| 2002 | 47.3 | 20 |
| 2001 | 44.3 | 20 |
| 2000 | 45.1 | 21 |
| 1999 | 47.9 | 20 |
| 1998 | 48.2 | 20 |
| 1997 | 45.7 | 20 |
| 1996 | 46.1 | 20 |
| 1995 | 41.8 | 22 |
| 1994 | 35.9 | 24 |
| 1993 | 33.6 | 24 |
| 1992 | 36.2 | 25 |
| 1991 | 31.5 | 25 |
| 1990 | 31.9 | 25 |
| 1989 | 25.6 | 25 |
| 1988 | 27.5 | 23 |
| 1987 | 24 | 26 |
| 1986 | 20 | 25 |