| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.52 | 52 |
| 2015 | 2.19 | 107 |
| 2014 | 2.56 | 109 |
| 2013 | 3.03 | 97 |
| 2012 | 2.82 | 104 |
| 2011 | 3.7 | 90 |
| 2010 | 3.99 | 73 |
| 2009 | 2.56 | 106 |
| 2008 | 3.73 | 108 |
| 2007 | 4.4 | 105 |
| 2006 | 4.51 | 91 |
| 2005 | 4.55 | 73 |
| 2004 | 3.48 | 83 |
| 2003 | 3.49 | 64 |
| 2002 | 3.61 | 69 |
| 2001 | 3.51 | 68 |
| 2000 | 3.48 | 83 |
| 1999 | 3.54 | 71 |
| 1998 | 4.25 | 51 |
| 1997 | 4.6 | 41 |
| 1996 | 4.65 | 29 |
| 1995 | 4.88 | 28 |
| 1994 | 5.99 | 13 |
| 1993 | 6.19 | 15 |
| 1992 | 2.61 | 31 |
| 1991 | 1.14 | 60 |
| 1990 | 0.97 | 68 |
| 1989 | 0.98 | 57 |
| 1988 | 1.02 | 50 |
| 1987 | 0.85 | 59 |
| 1986 | 0.62 | 56 |