| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.98 | 148 |
| 2015 | 2.36 | 116 |
| 2014 | 7.89 | 9 |
| 2013 | 11.65 | 4 |
| 2012 | 12.32 | 5 |
| 2011 | 17.29 | 2 |
| 2010 | 6.37 | 61 |
| 2009 | -1.27 | 118 |
| 2008 | 8.9 | 20 |
| 2007 | 10.25 | 23 |
| 2006 | 8.56 | 37 |
| 2005 | 7.25 | 48 |
| 2004 | 10.63 | 16 |
| 2003 | 7 | 45 |
| 2002 | 4.73 | 58 |
| 2001 | 2.95 | 101 |
| 2000 | 1.15 | 166 |
| 1999 | 3.07 | 108 |
| 1998 | 3.34 | 115 |
| 1997 | 3.9 | 109 |
| 1996 | 2.24 | 138 |
| 1995 | 6.38 | 48 |
| 1994 | 2.13 | 124 |
| 1993 | -3.17 | 158 |
| 1992 | -9.26 | 164 |
| 1991 | -8.69 | 167 |
| 1990 | -3.18 | 151 |
| 1989 | 4.18 | 73 |
| 1988 | 5.11 | 75 |
| 1987 | 3.46 | 81 |
| 1986 | 9.37 | 16 |