| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 16 | 189 |
| 2015 | 15.9 | 187 |
| 2014 | 15.7 | 184 |
| 2013 | 15.5 | 184 |
| 2012 | 15.4 | 184 |
| 2011 | 15.2 | 185 |
| 2010 | 15.1 | 185 |
| 2009 | 14.9 | 184 |
| 2008 | 14.8 | 184 |
| 2007 | 14.6 | 184 |
| 2006 | 14.5 | 183 |
| 2005 | 14.3 | 183 |
| 2004 | 14.2 | 183 |
| 2003 | 14 | 183 |
| 2002 | 13.8 | 183 |
| 2001 | 13.7 | 181 |
| 2000 | 13.5 | 181 |
| 1999 | 13.4 | 179 |
| 1998 | 13.2 | 179 |
| 1997 | 13.1 | 176 |
| 1996 | 12.9 | 176 |
| 1995 | 12.8 | 175 |
| 1994 | 12.6 | 173 |
| 1993 | 12.5 | 172 |
| 1992 | 12.3 | 171 |
| 1991 | 12.1 | 172 |
| 1990 | 12 | 169 |
| 1989 | 11.8 | 165 |
| 1988 | 11.6 | 165 |
| 1987 | 11.4 | 166 |
| 1986 | 11.3 | 166 |