| 1 | AMERICAN CAPITAL LTD. |
| 2 | CALVERT GROUP |
| 3 | CHEVY CHASE TRUST COMPANY |
| 4 | EAGLEBANK |
| 5 | HERITAGE INVESTORS MANAGEMENT CORP. |
| 6 | LOCKHEED MARTIN INVESTMENT MANAGEMENT COMPANY |
| 7 | MARRIOTT INTERNATIONAL, INC |
| 8 | POTOMAC ASSET MANAGEMENT INC. |
| 9 | ROCKLEDGE PARTNERS LLC |
| 10 | THE ITHAKA GROUP, LLC |
| 11 | VIAMERICAS CORPORATION |
| 12 | ZIRKIN-CUTLER INVESTMENTS, A DIVISION OF UNITED CAPITAL FINANCIAL ADVISERS |