| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 80 | 119 |
| 2015 | 77.8 | 121 |
| 2014 | 75.6 | 119 |
| 2013 | 73.3 | 121 |
| 2012 | 71.2 | 122 |
| 2011 | 69.1 | 123 |
| 2010 | 67.1 | 127 |
| 2009 | 65.2 | 129 |
| 2008 | 63.4 | 129 |
| 2007 | 61.7 | 129 |
| 2006 | 60 | 129 |
| 2005 | 58.4 | 128 |
| 2004 | 56.9 | 128 |
| 2003 | 55.4 | 129 |
| 2002 | 54 | 130 |
| 2001 | 52.6 | 131 |
| 2000 | 51.3 | 130 |
| 1999 | 50.1 | 128 |
| 1998 | 48.9 | 130 |
| 1997 | 47.8 | 128 |
| 1996 | 46.6 | 128 |
| 1995 | 45.4 | 129 |
| 1994 | 44.2 | 128 |
| 1993 | 43 | 128 |
| 1992 | 41.7 | 129 |
| 1991 | 40.5 | 130 |
| 1990 | 39.2 | 129 |
| 1989 | 38.1 | 127 |
| 1988 | 36.9 | 126 |
| 1987 | 35.8 | 127 |
| 1986 | 34.7 | 126 |