| Date | Acquired | Amount |
|---|---|---|
| Apr 28, 2016 |
|
$ 550,000,000 |
| Dec 01, 2014 |
|
$ 1,600,000,000 |
| Aug 20, 2012 |
|
$ 109,800,000 |
| Sep 12, 2008 |
|
$ 43,970,000 |
| Aug 01, 2002 |
|
Undisclosed amount |
| Jun 06, 2001 |
|
$ 225,000,000 |
| May 30, 2001 |
|
Undisclosed amount |
