| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 52.79 | 144 |
| 2014 | 53.9 | 148 |
| 2013 | 87.51 | 88 |
| 2012 | 90.62 | 88 |
| 2011 | 85.02 | 98 |
| 2010 | 67.95 | 130 |
| 2009 | 69.61 | 116 |
| 2008 | 88.52 | 93 |
| 2007 | 89.31 | 90 |
| 2006 | 80.34 | 110 |
| 2005 | 78.8 | 101 |
| 2004 | 128.22 | 29 |
| 2003 | 136.86 | 20 |
| 2002 | 141.55 | 15 |
| 2001 | 146.35 | 15 |
| 2000 | 199.68 | 8 |
| 1999 | 133.58 | 16 |
| 1998 | 106.92 | 36 |
| 1997 | 181.13 | 8 |
| 1996 | 156.63 | 10 |
| 1995 | 137.52 | 14 |
| 1994 | 97.65 | 44 |
| 1993 | 70.2 | 72 |
| 1992 | 22.23 | 158 |
| 1991 | 65.46 | 76 |
| 1990 | 62.96 | 81 |
| 1989 | 84.78 | 48 |
| 1988 | 81.4 | 47 |