performance of our business, identify trends affecting our business, develop projections and make strategic business decisions. Anon-GAAP financial measure is a numerical measure of a company’s operating performance, financial position or cash flow that excludes amounts that are included in the most directly comparable measure calculated and presented in accordance with GAAP or includes amounts that are excluded from the most directly comparable measure calculated and presented in accordance with GAAP.
Ournon-GAAP financial measures may not provide information that is directly comparable to that provided by other companies in our industry, as other companies in our industry may calculatenon-GAAP financial results differently. In addition, there are limitations in usingnon-GAAP financial measures because they are not prepared in accordance with GAAP and exclude expenses that may have a material impact on our reported financial results. For example, adjusted EBITDA excludes interest expense, which has been and will continue to be for the foreseeable future a significant recurring expense in our business. The presentation ofnon-GAAP financial information is not meant to be considered in isolation from, or as a substitute for, the most directly comparable financial measures prepared in accordance with GAAP. We urge you to review the additional information about adjusted EBITDA and free cash flow shown below, including the reconciliations of thesenon-GAAP financial measures to their comparable GAAP financial measures, and not to rely on any single financial measure to evaluate our business.
Adjusted EBITDA is anon-GAAP financial measure that we calculate as net (loss) income, excluding the impact of interest expense (net), income tax expense (benefit), depreciation, amortization of other intangible assets, stock-based compensation, restructuring expenses, transaction expenses and charges, (gain) loss of unconsolidated entities, impairment of other long-lived assets, SEC investigations reserve, and shareholder litigation reserve. We view adjusted EBITDA as a performance measure and believe it helps investors evaluate and compare our core operating performance from period to period.
Free Cash Flow, or FCF, is anon-GAAP financial measure that we calculate as cash flow from operations less capital expenditures and financed equipment obligations. We believe that FCF provides investors with an indicator of our ability to generate positive cash flows after meeting our obligations with regard to capital expenditures (including financed equipment obligations).
Key Operating Metrics
Total Subscribers – We define total subscribers as the approximate number of subscribers that, as of the end of a period, are identified as subscribing directly to our products on a paid basis, excluding accounts that access our solutions via resellers or that purchase only domain names from us. Subscribers of more than one brand, and subscribers with more than one distinct billing relationship or subscription with us, are counted as separate subscribers. Total subscribers for a period reflects adjustments to add or subtract subscribers as we integrate acquisitions and/or are otherwise able to identify subscribers that meet, or do not meet, this definition of total subscribers. In the second quarter of 2019, these adjustments had a negligible impact on our total subscriber count.
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