| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 24.8 | 170 |
| 2015 | 24.6 | 170 |
| 2014 | 24.4 | 167 |
| 2013 | 24.2 | 167 |
| 2012 | 24 | 167 |
| 2011 | 23.8 | 168 |
| 2010 | 23.5 | 168 |
| 2009 | 23.3 | 168 |
| 2008 | 23.1 | 168 |
| 2007 | 22.9 | 168 |
| 2006 | 22.6 | 168 |
| 2005 | 22.4 | 168 |
| 2004 | 22.1 | 168 |
| 2003 | 21.8 | 168 |
| 2002 | 21.6 | 169 |
| 2001 | 21.3 | 168 |
| 2000 | 21 | 167 |
| 1999 | 20.7 | 165 |
| 1998 | 20.4 | 164 |
| 1997 | 20 | 163 |
| 1996 | 19.7 | 163 |
| 1995 | 19.4 | 163 |
| 1994 | 19.1 | 162 |
| 1993 | 18.8 | 161 |
| 1992 | 18.5 | 160 |
| 1991 | 18.2 | 161 |
| 1990 | 17.9 | 158 |
| 1989 | 17.6 | 157 |
| 1988 | 17.2 | 157 |
| 1987 | 16.9 | 158 |
| 1986 | 16.6 | 158 |