In addition, any estimates relating to loss events involve the exercise of considerable judgment and reflect a combination of ground-up evaluations, information available to date from brokers and cedants, market intelligence, initial tentative loss reports and other sources. Due to the complexity of factors contributing to the losses and the preliminary nature of the information used to prepare these estimates, there can be no assurance that Aspen's ultimate losses will remain within the stated amount.Non-GAAP Financial Measures In presenting Aspen's results, management has included and discussed certain "non-GAAP financial measures" as such term is defined in Regulation G. Management believes that these non-GAAP measures, which may be defined differently by other companies, better explain Aspen's results of operations in a manner that allows for a more complete understanding of the underlying trends in Aspen's business. However, these measures should not be viewed as a substitute for those determined in accordance with GAAP. The reconciliation of such non-GAAP financial measures to their respective most directly comparable GAAP financial measures in accordance with Regulation G is included in the financial supplement, which can be obtained from the Investor Relations section of Aspen's website at www.aspen.co. (1) Annualized Operating Return on Average Equity (“Operating ROE”) is a non-GAAP financial measure. Annualized Operating Return on Average Equity is calculated using operating income, as defined below, and average equity calculated as the arithmetic average on a monthly basis for the stated periods of shareholders’ equity excluding the aggregate value of the liquidation preferences of our preference shares. Aspen presents Operating ROE as a measure that is commonly recognized as a standard of performance by investors, analysts, rating agencies and other users of its financial information. See page 26 of Aspen's financial supplement for a reconciliation of operating income to net income and page 8 for a reconciliation of average equity.