| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.2 | 156 |
| 2015 | 3 | 92 |
| 2014 | 3.6 | 88 |
| 2013 | 3.3 | 96 |
| 2012 | 7.2 | 28 |
| 2011 | 4.7 | 84 |
| 2010 | 2.2 | 139 |
| 2009 | -14.15 | 196 |
| 2008 | 6.9 | 45 |
| 2007 | 13.75 | 10 |
| 2006 | 13.2 | 8 |
| 2005 | 13.87 | 5 |
| 2004 | 10.47 | 17 |
| 2003 | 14.04 | 5 |
| 2002 | 13.19 | 3 |
| 2001 | 9.56 | 11 |
| 2000 | 5.9 | 48 |
| 1999 | 3.3 | 100 |
| 1998 | 7.3 | 27 |
| 1997 | 3.32 | 122 |
| 1996 | 5.87 | 59 |
| 1995 | 6.9 | 39 |
| 1994 | 5.4 | 53 |
| 1993 | -8.8 | 168 |
| 1992 | -41.8 | 177 |
| 1991 | -11.7 | 171 |