| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.42 | 30 |
| 2015 | 3.28 | 28 |
| 2014 | 3.28 | 27 |
| 2013 | 3.38 | 30 |
| 2012 | 3.29 | 29 |
| 2011 | 3.42 | 30 |
| 2010 | 4.31 | 39 |
| 2009 | 5.26 | 49 |
| 2008 | 3.56 | 37 |
| 2007 | 4.01 | 45 |
| 2006 | 4.77 | 53 |
| 2005 | 5.58 | 59 |
| 2004 | 6.74 | 73 |
| 2003 | 7.86 | 88 |
| 2002 | 7.28 | 85 |
| 2001 | 5.09 | 53 |
| 2000 | 4.92 | 52 |
| 1999 | 6.25 | 64 |
| 1998 | 4.58 | 45 |
| 1997 | 2.22 | 15 |
| 1996 | 2.83 | 23 |
| 1995 | 3.22 | 28 |
| 1994 | 1.9 | 13 |
| 1993 | 1.96 | 14 |
| 1992 | 1.96 | 11 |
| 1991 | 1.8 | 15 |