| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 18.46 | 112 |
| 2015 | 20.38 | 120 |
| 2014 | 24.95 | 98 |
| 2013 | 26.04 | 94 |
| 2012 | 27.31 | 81 |
| 2011 | 28.35 | 81 |
| 2010 | 25.32 | 100 |
| 2009 | 34.21 | 41 |
| 2008 | 41.48 | 27 |
| 2007 | 40.65 | 27 |
| 2006 | 41.92 | 26 |
| 2005 | 43.51 | 20 |
| 2004 | 42.09 | 19 |
| 2003 | 36.75 | 31 |
| 2002 | 30.52 | 66 |
| 2001 | 40.87 | 19 |
| 2000 | 52.21 | 8 |
| 1999 | 37.86 | 20 |
| 1998 | 33.56 | 37 |
| 1997 | 44.14 | 15 |
| 1996 | 48.52 | 10 |
| 1995 | 46.02 | 10 |
| 1994 | 32.86 | 47 |
| 1993 | 42.69 | 14 |
| 1992 | 53 | 6 |
| 1991 | 45.76 | 14 |
| 1990 | 45.27 | 17 |
| 1989 | 43.6 | 15 |
| 1988 | 31.79 | 47 |
| 1987 | 35.3 | 33 |
| 1986 | 27.16 | 57 |