| Year | Month | Dividend (%) |
|---|---|---|
| 2018 | Apr | 95 |
| 2017 | Apr | 90 |
| 2016 | May | 85 |
| 2015 | May | 80 |
| 2014 | May | 75 |
| 2013 | May | 74 |
| 2012 | May | 73 |
| 2011 | May | 72 |
| 2010 | May | 71 |
| 2009 | Apr | 70 |
| 2008 | Apr | 63 |
| 2007 | Apr | 53 |
| 2006 | Apr | 38 |
| 2005 | Jul | 12 |
| 2005 | Apr | 14 |
| 2005 | Jan | 11 |
| 2004 | Sep | 11 |
| 2004 | Jul | 11 |
| 2004 | Apr | 15 |
| 2004 | Jan | 10 |
| 2003 | Oct | 10 |
| 2003 | Jul | 10 |
| 2003 | Apr | 44 |
| 2002 | Jun | 43 |
| 2001 | Jun | 40 |
| 2000 | Mar | 37 |
| 1999 | May | 34 |
| 1998 | Jun | 32 |
| 1997 | Jul | 30 |