at the time of grant. The expected volatility is based on calculated enterprise value volatilities for publicly traded companies in the same industry and general stage of development. The estimated forfeiture rates were based on historical experience for similar classes of employees. The dividend yield was based on expected dividends at the time of grant.
Common stock warrant liability
Freestanding warrants related to shares that are redeemable, contingently redeemable, or for purchases of common stock that are not indexed to the Company’s own stock are classified as a liability on the Company’s balance sheet. The common stock warrants are recorded at fair value, estimated using the Black-Scholes option-pricing model, and marked to market at each balance sheet date with changes in the fair value of the liability recorded in other income (expense), net in the statements of operations.
A 10% change in the estimate of expected volatility at December 31, 2017 would increase or decrease the aggregate fair value of the common stock warrant liability in the amount of $45,000. A 10% change in the estimate of fair value of the common stock at December 31, 2017 would increase or decrease the aggregate fair value of the common stock warrant liability in the amount of $87,000.
Recently adopted accounting pronouncements
In March 2016, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, 2016-09, Improvements to Employee Share-Based Payment Accounting. ASU 2016-09 changes several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 requires all excess tax benefits and tax deficiencies to be recognized as income tax expense or benefit in the income statement and treated as discrete items in the reporting period. Further, excess tax benefits are required to be classified along with other income tax cash flows as an operating activity. The guidance was effective for the Company in the first quarter of 2017. Adoption of this guidance did not have a significant impact to the Company’s financial statements.
Recent accounting pronouncements not yet adopted
In May 2014, the FASB, issued ASU, 2014-09 (ASC 606), Revenue from Contracts with Customers. This ASU, as amended by ASU 2015-14, affects any entity that either enters into contracts with customers to transfer goods and services or enters into contracts for the transfer of nonfinancial assets. ASU 2014-09 will replace most existing revenue recognition guidance in GAAP when it becomes effective. The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies will need to use more judgment and make more estimates than under the currently effective guidance. These may include identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. ASU 2014-09 is effective for Exicure in the first quarter of 2018 and early adoption is permitted beginning in the first quarter of 2017. The Company intends to adopt this standard on January 1, 2018 on a modified retrospective basis and continues to analyze and assess the impact, if any, of this standard on its financial statements.
In February 2016, FASB issued ASU 2016-02, Leases (Topic 842), which requires lessees to recognize right-of-use assets and lease liabilities on the balance sheet. ASU 2016-02 is to be applied using a modified retrospective approach at the beginning of the earliest comparative period in the financial statements. ASU 2016-02 will be effective for the Company beginning in the first quarter of 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting this standard on its financial statements.
In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 addresses the classification of certain specific cash flow issues