| S. Atlantic Ocean, S. Pacific, S. Indian Ocean, Southern Ocean | ||||
| Year | 0 - 35 km | 35 - 70 km | 70 - 300 km | 300 - 500 km |
| 1996 | 0.4 | 0 | 0.5 | 0 |
| 1997 | 0.6 | 0 | 0.5 | 0 |
| 1998 | 0.5 | 0 | 0.5 | 0 |
| 1999 | 0.5 | 0 | 0.5 | 1 |
| 2000 | 0.6 | 0 | 0 | 0 |
| 2001 | 0.7 | 0 | 0 | 0 |
| 2002 | 0.8 | 0 | 0.8 | 0 |
| 2003 | 0.6 | 0 | 0.6 | 0 |
| 2004 | 0.7 | 0 | 1.3 | 1 |
| 2005 | 0.7 | 0 | 1 | 1 |
| 2006 | 0.7 | 0.7 | 1.3 | 0 |
| 2007 | 0.8 | 1 | 1.3 | 0 |
| 2008 | 1 | 1.2 | 0.9 | 0 |
| 2009 | 1 | 1 | 0.9 | 1 |
| 2010 | 3 | 8.2 | 1 | 1 |
| 2011 | 1 | 1.3 | 2 | 0 |
| 2012 | 1 | 1 | 1.7 | 0 |
| 2013 | 1.7 | 1.5 | 1.7 | 0 |
| 2014 | 1.6 | 1 | 1.6 | 0 |
| 2015 | 1.5 | 1.3 | 1.4 | 2 |
| 2016 | 1.9 | 1 | 1.4 | 2 |