| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 1.9 | 212 |
| 2015 | 1.9 | 212 |
| 2014 | 1.9 | 209 |
| 2013 | 1.8 | 209 |
| 2012 | 1.8 | 209 |
| 2011 | 1.8 | 210 |
| 2010 | 1.7 | 210 |
| 2009 | 1.7 | 210 |
| 2008 | 1.7 | 210 |
| 2007 | 1.7 | 210 |
| 2006 | 1.6 | 210 |
| 2005 | 1.6 | 210 |
| 2004 | 1.6 | 210 |
| 2003 | 1.6 | 210 |
| 2002 | 1.6 | 210 |
| 2001 | 1.6 | 210 |
| 2000 | 1.5 | 210 |
| 1999 | 1.5 | 208 |
| 1998 | 1.5 | 208 |
| 1997 | 1.5 | 207 |
| 1996 | 1.5 | 207 |
| 1995 | 1.5 | 207 |
| 1994 | 1.5 | 206 |
| 1993 | 1.5 | 206 |
| 1992 | 1.4 | 205 |
| 1991 | 1.4 | 206 |
| 1990 | 1.4 | 203 |
| 1989 | 1.4 | 201 |
| 1988 | 1.3 | 201 |
| 1987 | 1.3 | 201 |
| 1986 | 1.3 | 201 |