| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.98 | 24 |
| 2015 | 3.08 | 26 |
| 2014 | 3.27 | 26 |
| 2013 | 3.29 | 28 |
| 2012 | 3.29 | 30 |
| 2011 | 3.3 | 26 |
| 2010 | 3.32 | 24 |
| 2009 | 3.28 | 23 |
| 2008 | 3.31 | 34 |
| 2007 | 3.3 | 32 |
| 2006 | 2.33 | 15 |
| 2005 | 4 | 32 |
| 2004 | 3.22 | 24 |
| 2003 | 2.4 | 15 |
| 2002 | 3.26 | 25 |
| 2001 | 2.39 | 18 |
| 2000 | 2.74 | 24 |
| 1999 | 2.5 | 19 |
| 1998 | 2.5 | 14 |
| 1997 | 2.35 | 17 |
| 1996 | 2.46 | 18 |
| 1995 | 2.57 | 19 |
| 1994 | 2.6 | 20 |
| 1993 | 3.13 | 30 |
| 1992 | 2.36 | 17 |
| 1991 | 2.76 | 30 |