As our business includes the sourcing of passengers and deployment of vessels outside of North America, a portion of our revenue and expenses are denominated in foreign currencies, particularly euro and British pound sterling, which are subject to fluctuations in currency exchange rates versus our reporting currency, the U.S. dollar. In order to monitor results excluding these fluctuations, we calculate certain non-GAAP measures on a Constant Currency basis whereby current period revenue and expenses denominated in foreign currencies are converted to U.S. dollars using currency exchange rates of the comparable period. We believe that presenting these non-GAAP measures on both a reported and Constant Currency basis is useful in providing a more comprehensive view of trends in our business.
We believe that Adjusted EBITDA is appropriate as a supplemental financial measure as it is used by management to assess operating performance, is a factor in the evaluation of the performance of management and is the primary metric used in determining the Company's performance incentive bonus paid to its employees. We believe that Adjusted EBITDA is a useful measure in determining the Company's performance as it reflects certain operating drivers of the Company's business, such as sales growth, operating costs, marketing, general and administrative expenses and other operating income and expense. You are encouraged to evaluate each adjustment and the reasons we consider them appropriate for supplemental analysis. In evaluating Adjusted EBITDA, you should be aware that in the future we may incur expenses similar to the adjustments in this presentation. Our use of Adjusted EBITDA has limitations as an analytical tool, and you should not consider this measure in isolation or as a substitute for analysis of our results as reported under GAAP. Our presentation of Adjusted EBITDA should not be construed as an inference that our future results will be unaffected by unusual or non-recurring items.