| Date | Acquired | Amount |
|---|---|---|
| Oct 19, 2011 |
|
Undisclosed amount |
| Nov 18, 2010 |
|
$ 150,000,000 |
| Sep 20, 2007 |
|
$ 93,000,000 |
| Jun 28, 2004 |
|
$ 493,000,000 |
| Mar 31, 2004 |
|
Undisclosed amount |
| Jan 13, 2004 |
|
Undisclosed amount |
| Jun 26, 2000 |
|
$ 580,000,000 |
| Dec 17, 1999 |
|
Undisclosed amount |
| Nov 16, 1999 |
|
Undisclosed amount |
