| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 24.3 | 172 |
| 2015 | 24.1 | 172 |
| 2014 | 23.8 | 169 |
| 2013 | 23.6 | 169 |
| 2012 | 23.4 | 169 |
| 2011 | 23 | 171 |
| 2010 | 22.9 | 171 |
| 2009 | 22.7 | 169 |
| 2008 | 22.5 | 169 |
| 2007 | 22.3 | 169 |
| 2006 | 22.1 | 169 |
| 2005 | 22 | 169 |
| 2004 | 21.9 | 169 |
| 2003 | 21.8 | 169 |
| 2002 | 21.8 | 168 |
| 2001 | 21.7 | 166 |
| 2000 | 21.6 | 166 |
| 1999 | 21.6 | 163 |
| 1998 | 21.6 | 163 |
| 1997 | 21.6 | 161 |
| 1996 | 21.5 | 160 |
| 1995 | 21.5 | 160 |
| 1994 | 21.4 | 158 |
| 1993 | 21.2 | 158 |
| 1992 | 21.1 | 157 |
| 1991 | 21 | 157 |
| 1990 | 20.9 | 154 |
| 1989 | 20.7 | 152 |
| 1988 | 20.6 | 151 |
| 1987 | 20.5 | 150 |
| 1986 | 20.4 | 148 |