| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 29.3 | 169 |
| 2015 | 28.9 | 169 |
| 2014 | 28.5 | 166 |
| 2013 | 28.1 | 166 |
| 2012 | 27.8 | 166 |
| 2011 | 27.4 | 167 |
| 2010 | 27.1 | 167 |
| 2009 | 26.7 | 167 |
| 2008 | 26.2 | 167 |
| 2007 | 25.8 | 166 |
| 2006 | 25.3 | 166 |
| 2005 | 24.9 | 166 |
| 2004 | 24.5 | 166 |
| 2003 | 24.2 | 166 |
| 2002 | 23.8 | 164 |
| 2001 | 23.5 | 164 |
| 2000 | 23.1 | 163 |
| 1999 | 22.7 | 161 |
| 1998 | 22.3 | 161 |
| 1997 | 21.9 | 160 |
| 1996 | 21.5 | 161 |
| 1995 | 21 | 161 |
| 1994 | 20.5 | 160 |
| 1993 | 20 | 160 |
| 1992 | 19.5 | 159 |
| 1991 | 19 | 160 |
| 1990 | 18.5 | 157 |
| 1989 | 17.9 | 155 |
| 1988 | 17.4 | 156 |
| 1987 | 16.9 | 157 |
| 1986 | 16.4 | 159 |