| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.07 | 98 |
| 2015 | 1.09 | 106 |
| 2014 | 1.11 | 102 |
| 2013 | 1.12 | 104 |
| 2012 | 1.13 | 105 |
| 2011 | 1.1 | 101 |
| 2010 | 1.12 | 104 |
| 2009 | 1.21 | 105 |
| 2008 | 1.15 | 114 |
| 2007 | 1.18 | 110 |
| 2006 | 1.29 | 103 |
| 2005 | 1.38 | 100 |
| 2004 | 1.36 | 104 |
| 2003 | 1.47 | 92 |
| 2002 | 1.53 | 85 |
| 2001 | 1.48 | 87 |
| 2000 | 1.39 | 93 |
| 1999 | 1.27 | 100 |
| 1998 | 1.38 | 96 |
| 1997 | 1.58 | 84 |
| 1996 | 1.76 | 73 |
| 1995 | 2.12 | 64 |
| 1994 | 2.49 | 54 |
| 1993 | 2.42 | 58 |
| 1992 | 2.73 | 48 |
| 1991 | 3.13 | 41 |
| 1990 | 3.78 | 31 |
| 1989 | 4.22 | 28 |
| 1988 | 4.48 | 26 |
| 1987 | 4.06 | 31 |
| 1986 | 3.7 | 35 |