| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 46.7 | 150 |
| 2015 | 46.3 | 151 |
| 2014 | 45.9 | 148 |
| 2013 | 45.5 | 148 |
| 2012 | 45.1 | 147 |
| 2011 | 44.8 | 147 |
| 2010 | 44.5 | 145 |
| 2009 | 44.2 | 144 |
| 2008 | 44 | 144 |
| 2007 | 43.7 | 144 |
| 2006 | 43.5 | 144 |
| 2005 | 43.3 | 143 |
| 2004 | 43.1 | 143 |
| 2003 | 42.8 | 142 |
| 2002 | 42.6 | 140 |
| 2001 | 42.2 | 140 |
| 2000 | 41.7 | 140 |
| 1999 | 41 | 138 |
| 1998 | 40.3 | 137 |
| 1997 | 39.4 | 136 |
| 1996 | 38.5 | 137 |
| 1995 | 37.5 | 137 |
| 1994 | 36.5 | 137 |
| 1993 | 35.5 | 137 |
| 1992 | 34.6 | 139 |
| 1991 | 33.6 | 141 |