| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.2 | 118 |
| 2015 | 0.3 | 136 |
| 2014 | 14.42 | 41 |
| 2013 | 8.41 | 93 |
| 2012 | 10.94 | 73 |
| 2011 | 19.91 | 32 |
| 2010 | 13.55 | 72 |
| 2009 | 4.84 | 120 |
| 2008 | 16.04 | 72 |
| 2007 | 23.09 | 56 |
| 2006 | 19.64 | 75 |
| 2005 | 11.69 | 98 |
| 2004 | 10.45 | 102 |
| 2003 | 16.31 | 60 |
| 2002 | 18.05 | 54 |
| 2001 | 54.05 | 18 |
| 2000 | 14.13 | 76 |
| 1999 | 13.95 | 74 |
| 1998 | 19.57 | 35 |
| 1997 | 18.26 | 70 |
| 1996 | 14.64 | 81 |
| 1995 | 9.46 | 101 |
| 1994 | 15.7 | 84 |
| 1993 | 7.3 | 95 |
| 1992 | 31.27 | 33 |
| 1991 | 20.8 | 50 |
| 1990 | 11.42 | 74 |
| 1989 | 5.18 | 110 |
| 1988 | 13.6 | 77 |
| 1987 | 13.6 | 71 |
| 1986 | 1.41 | 110 |