MIME 2017 Annual Report

52 would be no practical interest or need on the behalf of a customer to buy these services without the underlying subscription. We do not have any knowledge of other vendors selling these services on a stand-alone basis and there is no way for an end-user to resell the deliverable. Accordingly, the deliverables within the arrangement including both subscription services and other professional services are accounted for as a single unit of accounting. On these occasions, revenue for the professional services deliverables in the arrangement is recognized on a straight-line basis over the contractual term or the average customer life, as further described below. Deferred revenue primarily consists of billings or payments received in advance of revenue recognition from subscription services described above and is recognized as the revenue recognition criteria are met. In addition, deferred revenue consists of amounts paid by customers related to upfront set-up or ingestion fees. Revenue related to such services is recognized over the contractual term or the average customer life, whichever is longer. The estimated customer life has been determined to be six years. Deferred revenue that is expected to be recognized during the succeeding twelve-month period is recorded as current deferred revenue and the remaining portion is recorded as non-current in the accompanying consolidated balance sheets. Income taxes We are subject to income tax in the United Kingdom, the United States and other international jurisdictions, and we use estimates in determining our provision for income taxes. We account for income taxes in accordance with ASC 740, Income Taxes . ASC 740 is an asset and liability approach that requires recognition of deferred tax assets and liabilities for the expected future tax consequences attributable to differences between the carrying amounts of assets and liabilities for financial reporting purposes and their respective tax basis, and for net operating loss and tax credit carryforwards. ASC 740 requires a valuation allowance against net deferred tax assets if, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. In making such determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax planning strategies and recent financial operations. Realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. Accordingly, the net deferred tax assets have been fully offset by a valuation allowance. We recognize the tax benefit from an uncertain tax position only if it is more likely than not the tax position will be sustained on examination by the tax authorities, based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such position are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement. As of March 31, 2018 and 2017, we did not have any uncertain tax positions that would impact our net tax provision if recognized. Accounting for share-based compensation awards We account for share-based compensation awards in accordance with the provisions of ASC 718, Compensation—Stock Compensation , which requires the recognition of expense related to the fair value of share-based compensation awards in the statements of operations. For service-based awards, we recognize share-based compensation expense on a straight-line basis over the requisite service period of the award. In connection with the adoption of ASU 2016-09 on April 1, 2017, we changed our accounting policy to record actual forfeitures as they occur, rather than estimating forfeitures by applying a forfeiture rate. This change has been applied on a modified retrospective basis, resulting in a cumulative effect adjustment on the date of adoption, which increased accumulated deficit and additional paid-in-capital by $0.1 million. For additional information, see Note 2 to the notes to our consolidated financial statements included elsewhere in this Annual Report on Form 10-K. Share Options We estimate the fair value of employee share options on the date of grant using the Black-Scholes option-pricing model, which requires the use of highly subjective estimates and assumptions. We estimate the expected term of share options for service-based awards utilizing the “Simplified Method,” as we do not have sufficient historical share option exercise information on which to base our estimate. The Simplified Method is based on the average of the vesting tranches and the contractual life of each grant. The risk- free interest rate is based on a treasury instrument whose term is consistent with the expected life of the share option. Since there was no public market for our ordinary shares prior to the IPO and as our shares have been publicly traded for a limited time, we determined the expected volatility for options granted based on an analysis of reported data for a peer group of companies that issue options with substantially similar terms. The expected volatility of options granted has been determined using an average of the historical volatility measures of this peer group of companies. We use an expected dividend rate of zero as we currently have no history or expectation of paying dividends on our ordinary shares. The grant date fair value of our ordinary shares at the time of each share option grant is based on the closing market value on the date of grant.