| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 5.31 | 40 |
| 2014 | 4.66 | 46 |
| 2013 | 3.66 | 74 |
| 2012 | 2.65 | 86 |
| 2011 | 3.13 | 101 |
| 2010 | 5.99 | 42 |
| 2009 | 2.87 | 83 |
| 2008 | 5.22 | 69 |
| 2007 | 5.91 | 45 |
| 2006 | 3.02 | 87 |
| 2005 | 2.69 | 74 |
| 2004 | 4.37 | 75 |
| 2003 | 3.5 | 66 |
| 2002 | 3.67 | 62 |
| 2001 | 3.73 | 65 |
| 2000 | 3.99 | 64 |
| 1999 | 4.95 | 58 |
| 1998 | 4.24 | 49 |
| 1997 | 8.3 | 15 |
| 1996 | 4.61 | 54 |
| 1995 | -1.64 | 104 |
| 1994 | 9.58 | 14 |
| 1993 | 12.41 | 12 |
| 1992 | 6 | 36 |
| 1991 | -4 | 104 |
| 1990 | -1 | 81 |
| 1989 | 7.11 | 19 |
| 1988 | -12.66 | 109 |
| 1987 | 0.51 | 66 |
| 1986 | 6.09 | 27 |