| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2013 | 1.76 | 74 |
| 2012 | 1.92 | 80 |
| 2011 | 2.11 | 82 |
| 2010 | 2.34 | 77 |
| 2009 | 2.59 | 36 |
| 2008 | 2.86 | 67 |
| 2007 | 3.17 | 81 |
| 2006 | 3.5 | 70 |
| 2005 | 3.87 | 62 |
| 2004 | 4.29 | 60 |
| 2003 | 4.8 | 42 |
| 2002 | 6.93 | 30 |
| 2001 | 2.86 | 49 |
| 2000 | 18.32 | 4 |
| 1999 | -10.6 | 125 |
| 1998 | 12.89 | 7 |
| 1997 | 31.38 | 1 |
| 1996 | -30.42 | 125 |
| 1995 | 18.62 | 5 |
| 1994 | -37.66 | 115 |
| 1993 | -36.55 | 109 |
| 1992 | -41.73 | 108 |
| 1991 | -14.97 | 102 |