Adjusted EBITDA is defined as income before interest expense (net of interest income), income taxes, depreciation and amortization, non-controlling interests, gain or loss on disposal of assets, equity method income, stock compensation, monitoring fees and expenses, realized gains or losses on investments, debt extinguishment costs, acquisition related expenses, impairment and restructuring charges and discontinued operations, net of taxes. Adjusted EBITDA is not intended as a substitute for net income (loss) attributable to Vanguard Health Systems, Inc. stockholders, operating cash flows or other cash flow statement data determined in accordance with accounting principles generally accepted in the United States. Due to varying methods of calculation, Adjusted EBITDA as presented may not be comparable to similarly titled measures of other companies. The following table provides a reconciliation of Adjusted EBITDA to net income (loss) attributable to Vanguard Health Systems, Inc. stockholders during the trailing twelve months ended September 30, 2011 (in millions).