| 时间 |
值 （亿美元） |
世界排名 |
| 2015 |
15.7 |
78 |
| 2014 |
17.5 |
76 |
| 2013 |
9.6 |
88 |
| 2012 |
8.3 |
105 |
| 2011 |
10.8 |
93 |
| 2010 |
8.7 |
92 |
| 2009 |
6.5 |
98 |
| 2008 |
15.9 |
87 |
| 2007 |
18.8 |
79 |
| 2006 |
11.7 |
81 |
| 2005 |
4.5 |
99 |
| 2004 |
4.9 |
85 |
| 2003 |
3.3 |
89 |
| 2002 |
1.6 |
99 |
| 2001 |
1.1 |
104 |
| 2000 |
1.3 |
99 |
| 1999 |
0.8 |
111 |
| 1998 |
2.7 |
80 |
| 1997 |
2.4 |
80 |