| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 50.4 | 144 |
| 2015 | 49.2 | 144 |
| 2014 | 48 | 143 |
| 2013 | 47 | 144 |
| 2012 | 45.9 | 146 |
| 2011 | 44.9 | 146 |
| 2010 | 43.9 | 147 |
| 2009 | 43 | 146 |
| 2008 | 42 | 146 |
| 2007 | 41.1 | 147 |
| 2006 | 40.2 | 146 |
| 2005 | 39.4 | 145 |
| 2004 | 38.6 | 146 |
| 2003 | 37.9 | 147 |
| 2002 | 37.2 | 147 |
| 2001 | 36.5 | 148 |
| 2000 | 35.8 | 148 |
| 1999 | 35.2 | 146 |
| 1998 | 34.6 | 145 |
| 1997 | 33.9 | 144 |
| 1996 | 33.1 | 145 |
| 1995 | 32 | 146 |
| 1994 | 30.7 | 145 |
| 1993 | 29.2 | 146 |
| 1992 | 27.5 | 147 |
| 1991 | 25.9 | 150 |
| 1990 | 24.6 | 148 |
| 1989 | 23.5 | 146 |
| 1988 | 22.6 | 146 |
| 1987 | 21.9 | 146 |
| 1986 | 21.3 | 146 |