| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 97.8 | 5 |
| 2015 | 124.3 | 5 |
| 2014 | 99.9 | 8 |
| 2013 | 81.9 | 8 |
| 2012 | 86.9 | 8 |
| 2011 | 109.4 | 9 |
| 2010 | 117.3 | 7 |
| 2009 | 89.1 | 12 |
| 2008 | 182.1 | 10 |
| 2007 | 126.6 | 9 |
| 2006 | 113.3 | 9 |
| 2005 | 102.2 | 7 |
| 2004 | 91.5 | 13 |
| 2003 | 85.1 | 9 |
| 2002 | 98.3 | 10 |
| 2001 | 318.3 | 1 |
| 2000 | 314.1 | 2 |
| 1999 | 87 | 5 |
| 1998 | 27 | 39 |
| 1997 | 20.1 | 41 |
| 1996 | 13.2 | 33 |
| 1995 | 10.5 | 35 |
| 1994 | 13.7 | 31 |
| 1993 | 12.4 | 31 |
| 1992 | 12.5 | 24 |
| 1991 | 13.1 | 23 |
| 1990 | 14.6 | 24 |
| 1989 | 16.9 | 19 |
| 1988 | 15.1 | 21 |
| 1987 | 29.7 | 16 |
| 1986 | 16.6 | 18 |