| Date |
Changes |
| May 18, 2012 |
-0.5 of a percentage point |
| February 24, 2012 |
-0.5 of a percentage point |
| December 5, 2011 |
-0.5 of a percentage point |
| June 20, 2011 |
+0.5 of a percentage point |
| May 18, 2011 |
+0.5 of a percentage point |
| April 21, 2011 |
+0.5 of a percentage point |
| March 25, 2011 |
+0.5 of a percentage point |
| February 24, 2011 |
+0.5 of a percentage point |
| January 20, 2011 |
+0.5 of a percentage point |
| December 20, 2010 |
+0.5 of a percentage point |
| November 29, 2010 |
+0.5 of a percentage point |
| November 29, 2010 |
+0.5 of a percentage point |
| May 10, 2010 |
+0.5 of a percentage point |
| February 25, 2010 |
+0.5 of a percentage point |
| January 18, 2010 |
+0.5 of a percentage point |