| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.232 | 55 |
| 2015 | 3.731 | 60 |
| 2014 | 4.012 | 62 |
| 2013 | 3.827 | 70 |
| 2012 | 4.108 | 71 |
| 2011 | 4.272 | 68 |
| 2010 | 4.583 | 66 |
| 2009 | 4.04 | 88 |
| 2008 | 7.551 | 54 |
| 2007 | 7.784 | 46 |
| 2006 | 6.915 | 50 |
| 2005 | 6.683 | 50 |
| 2004 | 5.77 | 57 |
| 2003 | 5.098 | 70 |
| 2002 | 5.332 | 72 |
| 2001 | 5.35 | 81 |
| 2000 | 6.36 | 83 |
| 1999 | 4.558 | 112 |
| 1998 | 6.777 | 90 |
| 1997 | 7.261 | 81 |
| 1996 | 8.489 | 76 |
| 1995 | 8.491 | 72 |
| 1994 | 6.375 | 85 |
| 1993 | 6.242 | 86 |
| 1992 | 6.583 | 83 |
| 1991 | 8.925 | 59 |
| 1990 | 11.65 | 44 |
| 1989 | 10.92 | 46 |
| 1988 | 13.41 | 28 |
| 1986 | 16.321 | 19 |