| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.83 | 88 |
| 2015 | 2.79 | 101 |
| 2014 | 3.34 | 93 |
| 2013 | 2.9 | 102 |
| 2012 | 2.29 | 117 |
| 2011 | 3.68 | 104 |
| 2010 | 6.5 | 57 |
| 2009 | 0.71 | 94 |
| 2008 | 2.83 | 124 |
| 2007 | 5.46 | 107 |
| 2006 | 5.18 | 109 |
| 2005 | 3.92 | 121 |
| 2004 | 4.9 | 106 |
| 2003 | 2.93 | 128 |
| 2002 | 7.43 | 19 |
| 2001 | 4.53 | 58 |
| 2000 | 8.92 | 18 |
| 1999 | 11.31 | 8 |
| 1998 | -5.47 | 188 |
| 1997 | 5.92 | 55 |
| 1996 | 7.59 | 31 |
| 1995 | 9.57 | 14 |
| 1994 | 9.21 | 13 |
| 1993 | 6.85 | 29 |
| 1992 | 6.18 | 43 |
| 1991 | 10.35 | 8 |
| 1990 | 9.81 | 14 |
| 1989 | 7.03 | 29 |
| 1988 | 11.9 | 12 |
| 1987 | 12.47 | 9 |
| 1986 | 11.22 | 9 |