hotel property during the year ended December 31, 2017. During the year ended December 31, 2016, we recognized a net gain on the sale of hotel properties of $45.9 million, which was due to the sale of four hotel properties.
Gain on Settlement of an Investment in Loan
During the year ended December 31, 2017, we recognized a gain on settlement of an investment in loan of approximately $2.7 million as a result of the investment in loan maturing in September 2017.
As part of our structure, we own TRSs that are subject to federal and state income taxes. Income tax expense increased $33.9 million to $42.1 million for the year ended December 31, 2017 from $8.2 million for the year ended December 31, 2016. The increase was primarily due to the impact of the Tax Cuts and Jobs Act (the "Tax Reform Act"), which was signed into law on December 22, 2017. The Tax Reform Act reduced the corporate income tax rate from 35% to 21%. The enactment of the Tax Reform Act resulted in a $31.7 million increase in our deferred tax expense as the lower corporate income tax rates that are expected to be in effect in the future reduced the future realizable value of our net deferred tax assets.
Non-GAAP Financial Measures
We consider the following non-GAAP financial measures useful to investors as key supplemental measures of our performance: (1) FFO, (2) Adjusted FFO, (3) EBITDA, (4) EBITDAre and (5) Adjusted EBITDA. These non-GAAP financial measures should be considered along with, but not as alternatives to, net income or loss as a measure of our operating performance. FFO, Adjusted FFO, EBITDA, EBITDAre, and Adjusted EBITDA, as calculated by us, may not be comparable to FFO, Adjusted FFO, EBITDA, EBITDAre and Adjusted EBITDA as reported by other companies that do not define such terms exactly as we define such terms.
Funds From Operations
We calculate funds from operations ("FFO") in accordance with standards established by the National Association of Real Estate Investment Trusts ("NAREIT"), which defines FFO as net income or loss, excluding gains or losses from sales of real estate, impairment, the cumulative effect of changes in accounting principles, plus depreciation and amortization, and adjustments for unconsolidated partnerships and joint ventures. Historical cost accounting for real estate assets implicitly assumes that the value of real estate assets diminishes predictably over time. Since real estate values instead have historically risen or fallen with market conditions, most real estate industry investors consider FFO to be helpful in evaluating a real estate company’s operations. We believe that the presentation of FFO provides useful information to investors regarding our operating performance and can facilitate comparisons of operating performance between periods and between REITs, even though FFO does not represent an amount that accrues directly to common shareholders. Our calculation of FFO may not be comparable to measures calculated by other companies who do not use the NAREIT definition of FFO or do not calculate FFO per diluted share in accordance with NAREIT guidance. Additionally, FFO may not be helpful when comparing us to non-REITs. We present FFO attributable to common shareholders, which includes our OP units, because our OP units may be redeemed for common shares. We believe it is meaningful for the investor to understand FFO attributable to all common shares and OP units.
We further adjust FFO for certain additional items that are not in NAREIT’s definition of FFO, such as hotel transaction costs, non-cash income tax expense or benefit, the amortization of share-based compensation, and certain other income or expenses that we consider outside the normal course of operations. We believe that Adjusted FFO provides useful supplemental information to investors regarding our ongoing operating performance that, when considered with net income and FFO, is beneficial to an investor’s understanding of our operating performance.