| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 77.7 | 122 |
| 2015 | 77.9 | 120 |
| 2014 | 78.2 | 115 |
| 2013 | 78.5 | 113 |
| 2012 | 78.7 | 110 |
| 2011 | 78.9 | 110 |
| 2010 | 79.2 | 110 |
| 2009 | 79.5 | 108 |
| 2008 | 79.8 | 107 |
| 2007 | 80.3 | 105 |
| 2006 | 80.8 | 103 |
| 2005 | 81.3 | 100 |
| 2004 | 81.9 | 100 |
| 2003 | 82.5 | 99 |
| 2002 | 83.2 | 98 |
| 2001 | 84 | 97 |
| 2000 | 84.9 | 95 |
| 1999 | 85.7 | 93 |
| 1998 | 86.6 | 90 |
| 1997 | 87.3 | 89 |
| 1996 | 88.1 | 89 |
| 1995 | 88.9 | 89 |
| 1994 | 89.6 | 88 |
| 1993 | 90.1 | 87 |
| 1992 | 90 | 85 |
| 1991 | 89.8 | 85 |
| 1990 | 89.6 | 81 |
| 1989 | 89.4 | 79 |
| 1988 | 88.9 | 79 |
| 1987 | 88.5 | 78 |
| 1986 | 88.2 | 77 |