| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 17.8 | 184 |
| 2015 | 17.5 | 184 |
| 2014 | 17.1 | 180 |
| 2013 | 16.9 | 180 |
| 2012 | 16.7 | 180 |
| 2011 | 16.6 | 181 |
| 2010 | 16.5 | 181 |
| 2009 | 16.3 | 181 |
| 2008 | 16.2 | 181 |
| 2007 | 16 | 181 |
| 2006 | 15.9 | 181 |
| 2005 | 15.7 | 180 |
| 2004 | 15.5 | 180 |
| 2003 | 15.3 | 180 |
| 2002 | 15 | 179 |
| 2001 | 14.7 | 179 |
| 2000 | 14.7 | 176 |
| 1999 | 14.6 | 173 |
| 1998 | 14.5 | 173 |
| 1997 | 14.4 | 171 |
| 1996 | 14.2 | 171 |
| 1995 | 14 | 171 |
| 1994 | 13.7 | 170 |
| 1993 | 13.6 | 170 |
| 1992 | 13.4 | 169 |
| 1991 | 13.3 | 169 |
| 1990 | 12.6 | 166 |
| 1989 | 12.5 | 164 |
| 1988 | 12.5 | 164 |
| 1987 | 12.4 | 164 |
| 1986 | 12.3 | 164 |