| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 8.39 | 12 |
| 2015 | -.06 | 130 |
| 2014 | -3.52 | 158 |
| 2013 | 1.53 | 115 |
| 2012 | 2.43 | 87 |
| 2011 | 4.47 | 83 |
| 2010 | 2.32 | 127 |
| 2009 | -3.14 | 93 |
| 2008 | 9.42 | 27 |
| 2007 | 1.67 | 126 |
| 2006 | 2.28 | 128 |
| 2005 | 3.76 | 95 |
| 2004 | 2.99 | 116 |
| 2003 | 0.08 | 141 |
| 2002 | 5.08 | 63 |
| 2001 | 5.15 | 51 |
| 2000 | 4.41 | 80 |
| 1999 | 6.24 | 46 |
| 1998 | 4.84 | 62 |
| 1997 | 3.31 | 90 |
| 1996 | 7.97 | 28 |
| 1995 | 6.76 | 41 |
| 1994 | 1.91 | 92 |
| 1993 | 7.07 | 29 |
| 1992 | 1.11 | 72 |
| 1991 | -.93 | 86 |
| 1990 | 3.53 | 51 |
| 1989 | 3.11 | 66 |
| 1988 | 3.06 | 67 |
| 1987 | 3.23 | 62 |