| 时间 | 值 （人/平方公里） | 世界排名 |
|---|---|---|
| 2016 | 227.4 | 53 |
| 2015 | 220.9 | 53 |
| 2014 | 212.3 | 53 |
| 2013 | 201.9 | 57 |
| 2012 | 190.5 | 59 |
| 2011 | 179.1 | 60 |
| 2010 | 168.2 | 63 |
| 2009 | 158.2 | 64 |
| 2008 | 148.8 | 66 |
| 2007 | 140.5 | 67 |
| 2006 | 133.4 | 69 |
| 2005 | 127.8 | 71 |
| 2004 | 123.9 | 74 |
| 2003 | 121.7 | 75 |
| 2002 | 120.3 | 74 |
| 2001 | 118.4 | 75 |
| 2000 | 115.1 | 75 |
| 1999 | 109.8 | 78 |
| 1998 | 103.1 | 81 |
| 1997 | 96.3 | 86 |
| 1996 | 91.6 | 88 |
| 1995 | 90.4 | 88 |
| 1991 | 114.2 | 68 |
| 1990 | 117.8 | 64 |
| 1989 | 117.7 | 61 |
| 1988 | 114.4 | 62 |
| 1987 | 109 | 65 |
| 1986 | 103 | 68 |