| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 22.3 | 177 |
| 2015 | 21.7 | 178 |
| 2014 | 21 | 175 |
| 2013 | 20.4 | 175 |
| 2012 | 19.8 | 175 |
| 2011 | 19.2 | 179 |
| 2010 | 18.6 | 179 |
| 2009 | 18.1 | 178 |
| 2008 | 17.6 | 178 |
| 2007 | 17.1 | 179 |
| 2006 | 16.7 | 179 |
| 2005 | 16.2 | 179 |
| 2004 | 15.8 | 179 |
| 2003 | 15.4 | 179 |
| 2002 | 15 | 180 |
| 2001 | 14.6 | 180 |
| 2000 | 14.2 | 180 |
| 1999 | 13.8 | 178 |
| 1998 | 13.4 | 178 |
| 1997 | 13 | 177 |
| 1996 | 12.6 | 177 |
| 1995 | 12.3 | 177 |
| 1994 | 12 | 177 |
| 1993 | 11.7 | 178 |
| 1992 | 11.4 | 178 |
| 1991 | 11.1 | 179 |
| 1990 | 10.8 | 176 |
| 1989 | 10.5 | 174 |
| 1988 | 10.2 | 174 |
| 1987 | 9.9 | 174 |
| 1986 | 9.6 | 174 |