| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 21.12 | 178 |
| 2014 | 30.89 | 179 |
| 2013 | 31.05 | 183 |
| 2012 | 44.38 | 173 |
| 2011 | 52.79 | 162 |
| 2010 | 42.65 | 174 |
| 2009 | 61.8 | 132 |
| 2008 | 64.97 | 138 |
| 2007 | 64.46 | 138 |
| 2006 | 64.61 | 137 |
| 2005 | 50.75 | 159 |
| 2004 | 48.45 | 160 |
| 2003 | 75.22 | 101 |
| 2002 | 63.38 | 122 |
| 2001 | 81.81 | 79 |
| 2000 | 71.38 | 101 |
| 1999 | 55.85 | 120 |
| 1998 | 66.17 | 102 |
| 1997 | 76.86 | 87 |
| 1996 | 57.69 | 113 |
| 1995 | 59.77 | 112 |
| 1994 | 42.31 | 138 |
| 1993 | 58.11 | 96 |
| 1992 | 61.03 | 89 |
| 1991 | 64.88 | 77 |
| 1990 | 53.03 | 99 |
| 1989 | 60.39 | 76 |
| 1988 | 35.31 | 119 |
| 1987 | 41.65 | 103 |
| 1986 | 23.72 | 127 |