| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.28 | 68 |
| 2015 | 1.51 | 88 |
| 2014 | 2.49 | 93 |
| 2013 | 2.45 | 98 |
| 2012 | 1.76 | 151 |
| 2011 | 3.3 | 134 |
| 2010 | 2.85 | 105 |
| 2009 | 1.82 | 115 |
| 2008 | 4.35 | 146 |
| 2007 | 2.33 | 138 |
| 2006 | 3.54 | 106 |
| 2005 | 2.67 | 122 |
| 2004 | 2.34 | 114 |
| 2003 | 2.77 | 97 |
| 2002 | 3 | 89 |
| 2001 | 4.38 | 78 |
| 2000 | 4.48 | 66 |
| 1999 | 1.47 | 115 |
| 1998 | 0.85 | 144 |
| 1997 | 0.25 | 160 |
| 1996 | 2.61 | 124 |
| 1995 | 4.64 | 114 |
| 1994 | 1.89 | 135 |
| 1993 | 1.81 | 125 |
| 1992 | 0.99 | 129 |
| 1991 | 3.22 | 112 |
| 1990 | 7.27 | 77 |
| 1989 | 7.56 | 67 |
| 1988 | 7.23 | 67 |
| 1987 | 8.49 | 56 |
| 1986 | 9.08 | 52 |