| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 8.8 | 199 |
| 2015 | 8.8 | 199 |
| 2014 | 8.8 | 196 |
| 2013 | 8.8 | 196 |
| 2012 | 8.7 | 196 |
| 2011 | 8.7 | 197 |
| 2010 | 8.7 | 197 |
| 2009 | 8.7 | 197 |
| 2008 | 8.7 | 197 |
| 2007 | 8.7 | 194 |
| 2006 | 8.7 | 194 |
| 2005 | 8.8 | 194 |
| 2004 | 8.8 | 194 |
| 2003 | 8.8 | 194 |
| 2002 | 8.9 | 194 |
| 2001 | 8.9 | 194 |
| 2000 | 8.9 | 194 |
| 1999 | 9 | 190 |
| 1998 | 9 | 189 |
| 1997 | 9 | 188 |
| 1996 | 9 | 187 |
| 1995 | 9.1 | 186 |
| 1994 | 9.1 | 184 |
| 1993 | 9.1 | 184 |
| 1992 | 9.1 | 183 |
| 1991 | 9.1 | 184 |
| 1990 | 9 | 181 |
| 1989 | 9 | 179 |
| 1988 | 9 | 178 |
| 1987 | 8.9 | 177 |
| 1986 | 8.8 | 176 |