| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 34.74 | 3 |
| 2015 | 10.28 | 13 |
| 2014 | 7.28 | 25 |
| 2013 | 8.78 | 16 |
| 2012 | 10.29 | 21 |
| 2011 | 13.47 | 19 |
| 2010 | 14.47 | 4 |
| 2009 | 13.73 | 6 |
| 2008 | 12.47 | 46 |
| 2007 | 12.25 | 15 |
| 2006 | 13.3 | 9 |
| 2005 | 22.96 | 4 |
| 2004 | 43.54 | 3 |
| 2003 | 98.22 | 2 |
| 2002 | 108.9 | 2 |
| 2001 | 152.56 | 2 |
| 2000 | 325 | 2 |
| 1999 | 248.2 | 3 |
| 1998 | 107.28 | 1 |
| 1997 | 219.18 | 2 |
| 1996 | 4145.11 | 1 |
| 1995 | 2671.79 | 1 |
| 1994 | 948.81 | 7 |
| 1993 | 1379.41 | 5 |
| 1992 | 299.06 | 3 |
| 1991 | 83.61 | 13 |