| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 35.2 | 164 |
| 2015 | 35.1 | 164 |
| 2014 | 35 | 158 |
| 2013 | 34.9 | 157 |
| 2012 | 34.9 | 157 |
| 2011 | 34.8 | 158 |
| 2010 | 34.8 | 157 |
| 2009 | 34.8 | 157 |
| 2008 | 34.7 | 157 |
| 2007 | 34.7 | 155 |
| 2006 | 34.7 | 154 |
| 2005 | 34.6 | 153 |
| 2004 | 34.5 | 153 |
| 2003 | 34.4 | 153 |
| 2002 | 34.2 | 151 |
| 2001 | 34 | 151 |
| 2000 | 33.9 | 150 |
| 1999 | 33.6 | 147 |
| 1998 | 33.4 | 147 |
| 1997 | 33.1 | 145 |
| 1996 | 33 | 146 |
| 1995 | 33 | 145 |
| 1994 | 33.1 | 143 |
| 1993 | 33.4 | 141 |
| 1992 | 33.7 | 141 |
| 1991 | 34 | 139 |
| 1990 | 34.1 | 137 |
| 1989 | 34 | 133 |
| 1988 | 33.8 | 133 |
| 1987 | 33.4 | 133 |
| 1986 | 33 | 132 |