approximately $6.2 million of net unfavorable foreign currency impact to our Americas adjusted EBITDA primarily due to a generally stronger U.S. dollar relative to the Brazilian Real during the nine months ended September 30, 2018 compared to the nine months ended September 30, 2017.
EMEA Adjusted EBITDA. The increase in our EMEA adjusted EBITDA was primarily due to higher revenues as a result of our IBX data center expansion activity and acquisitions, as described above, as well as lower sales and marketing and general and administrative expenses as a percentage of revenues. During the nine months ended September 30, 2018, foreign currency fluctuations resulted in approximately $32.5 million of net favorable foreign currency impact to our EMEA adjusted EBITDA primarily due to a generally weaker U.S. dollar relative to the Euro and British Pound during the nine months ended September 30, 2018 compared to the nine months ended September 30, 2017.
Asia-Pacific Adjusted EBITDA. The increase in our Asia-Pacific adjusted EBITDA was primarily due to the Metronode Acquisition, higher revenues as a result of our IBX data center expansion activity and organic growth as described above and lower cost of revenues as a percentage of revenues. During the nine months ended September 30, 2018, foreign currency fluctuations resulted in approximately $6.8 million of net favorable foreign currency impact to our Asia-Pacific adjusted EBITDA primarily due to a generally weaker U.S. dollar relative to Japanese Yen and Singapore Dollar during the nine months ended September 30, 2018 compared to the nine months ended September 30, 2017.
Non-GAAP Financial Measures
We provide all information required in accordance with GAAP, but we believe that evaluating our ongoing operating results may be difficult if limited to reviewing only GAAP financial measures. Accordingly, we use non-GAAP financial measures to evaluate our operations.
Non-GAAP financial measures are not a substitute for financial information prepared in accordance with GAAP. Non-GAAP financial measures should not be considered in isolation but should be considered together with the most directly comparable GAAP financial measures and the reconciliation of the non-GAAP financial measures to the most directly comparable GAAP financial measures. We have presented such non-GAAP financial measures to provide investors with an additional tool to evaluate our operating results in a manner that focuses on what management believes to be our core, ongoing business operations. We believe that the inclusion of these non-GAAP financial measures provides consistency and comparability with past reports and provides a better understanding of the overall performance of the business and ability to perform in subsequent periods. We believe that if we did not provide such non-GAAP financial information, investors would not have all the necessary data to analyze Equinix effectively.
Investors should note that the non-GAAP financial measures used by us may not be the same non-GAAP financial measures, and may not be calculated in the same manner, as those of other companies. Investors should therefore exercise caution when comparing non-GAAP financial measures used by us to similarly titled non-GAAP financial measures of other companies.
Our primary non-GAAP financial measures, adjusted EBITDA and adjusted funds from operations ("AFFO"), exclude depreciation expense as these charges primarily relate to the initial construction costs of our IBX data centers and do not reflect our current or future cash spending levels to support our business. Our IBX data centers are long-lived assets and have an economic life greater than 10 years. The construction costs of an IBX data center do not recur with respect to such data center, although we may incur initial construction costs in future periods with respect to additional IBX data centers, and future capital expenditures remain minor relative to our initial investment. This is a trend we expect to continue. In addition, depreciation is also based on the estimated useful lives of our IBX data centers. These estimates could vary from actual performance of the asset, are based on historical costs incurred to build out our IBX data centers and are not indicative of current or expected future capital expenditures. Therefore, we exclude depreciation from our operating results when evaluating our operations.
In addition, in presenting adjusted EBITDA and AFFO, we exclude amortization expense related to acquired intangible assets. Amortization expense is significantly affected by the timing and magnitude of our acquisitions and these charges may vary in amount from period to period. We exclude amortization expense to facilitate a more meaningful evaluation of our current operating performance and comparisons to our prior periods. We exclude accretion expense, both as it relates to asset retirement obligations as well as accrued restructuring charge liabilities, as these expenses represent costs which we believe are not meaningful in evaluating our current operations. We exclude stock-based compensation expense, as it can vary significantly from period to period based on share price, the timing, size and nature of equity awards. As such, we, and many investors and analysts, exclude stock-based compensation expense to compare our operating results with those of other companies. We also exclude restructuring charges. The restructuring charges relate to our decisions to exit leases for excess space adjacent to several of our IBX data centers, which we did not intend to build out, or our decision to reverse such restructuring charges. We also exclude impairment charges related to certain long-lived assets. The impairment charges are related to expense recognized whenever events or changes in circumstances indicate that the carrying amount of long-lived assets are not recoverable. We also exclude gain or loss on asset sales as it represents