| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.29 | 113 |
| 2015 | 2.27 | 136 |
| 2014 | 2.08 | 141 |
| 2013 | 2.26 | 143 |
| 2012 | 2.23 | 140 |
| 2011 | 2.46 | 137 |
| 2010 | 2.39 | 139 |
| 2009 | 2.26 | 140 |
| 2008 | 2.42 | 139 |
| 2007 | 2.34 | 141 |
| 2006 | 2.61 | 138 |
| 2005 | 3.13 | 135 |
| 2004 | 3.51 | 134 |
| 2003 | 3.78 | 129 |
| 2002 | 4.2 | 128 |
| 2001 | 4.26 | 127 |
| 2000 | 4 | 128 |
| 1999 | 4.21 | 122 |
| 1998 | 4.67 | 120 |
| 1997 | 4.25 | 126 |
| 1996 | 4.99 | 122 |
| 1995 | 5.23 | 124 |
| 1994 | 5.07 | 111 |
| 1993 | 5.61 | 106 |
| 1992 | 5.72 | 104 |
| 1991 | 6.19 | 101 |
| 1990 | 6.86 | 100 |
| 1989 | 6.93 | 90 |
| 1988 | 7.17 | 88 |
| 1987 | 7.43 | 87 |
| 1986 | 7.33 | 84 |