| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 49.2 | 147 |
| 2015 | 48.8 | 145 |
| 2014 | 48.5 | 141 |
| 2013 | 48.2 | 141 |
| 2012 | 47.8 | 139 |
| 2011 | 47.5 | 140 |
| 2010 | 47.1 | 140 |
| 2009 | 46.6 | 141 |
| 2008 | 46.2 | 141 |
| 2007 | 45.7 | 142 |
| 2006 | 45.3 | 142 |
| 2005 | 45 | 139 |
| 2004 | 44.8 | 139 |
| 2003 | 44.7 | 139 |
| 2002 | 44.6 | 138 |
| 2001 | 44.6 | 137 |
| 2000 | 44.4 | 136 |
| 1999 | 44.1 | 133 |
| 1998 | 43.8 | 133 |
| 1997 | 43.4 | 131 |
| 1996 | 42.9 | 131 |
| 1995 | 42.4 | 131 |
| 1994 | 41.9 | 130 |
| 1993 | 41.3 | 130 |
| 1992 | 40.8 | 131 |
| 1991 | 40.3 | 131 |
| 1990 | 39.9 | 128 |
| 1989 | 39.7 | 124 |
| 1988 | 39.6 | 122 |
| 1987 | 39.5 | 122 |
| 1986 | 39.3 | 120 |