| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.47 | 72 |
| 2015 | 5.59 | 139 |
| 2014 | 5.74 | 152 |
| 2013 | 5.79 | 166 |
| 2012 | 5.71 | 166 |
| 2011 | 5.99 | 167 |
| 2010 | 6.44 | 163 |
| 2009 | 6.34 | 163 |
| 2008 | 7.23 | 157 |
| 2007 | 7.42 | 155 |
| 2006 | 7.24 | 154 |
| 2005 | 7.63 | 153 |
| 2004 | 8.19 | 143 |
| 2003 | 7.76 | 141 |
| 2002 | 8.74 | 138 |
| 2001 | 9.45 | 130 |
| 2000 | 11.61 | 110 |
| 1999 | 9.76 | 122 |
| 1998 | 6.89 | 130 |
| 1997 | 6.86 | 129 |
| 1996 | 7.21 | 130 |
| 1995 | 7.86 | 124 |
| 1994 | 7.9 | 115 |
| 1993 | 9.16 | 104 |
| 1992 | 8.57 | 102 |
| 1991 | 8.57 | 97 |
| 1990 | 8.81 | 91 |
| 1989 | 8.22 | 94 |
| 1988 | 8.01 | 92 |
| 1987 | 7.67 | 94 |
| 1986 | 6.69 | 97 |