Note 15. Income Taxes

The components of income tax expense (benefit) are as follows:

Significant components of the Company's deferred income tax assets and liabilities are as follows:

A valuation allowance is established if it is more likely than not that all or a portion of the deferred tax asset will not be realized. The Company recorded a valuation allowance at April 30, 2019 and 2018 due to the uncertainty of realization. Management believes that based upon its projection of future taxable operating income for the foreseeable future, it is more likely than not that the Company will not be able to realize the tax benefit associated with deferred tax assets. The net change in the valuation allowance during the year ended April 30, 2019 was an increase of $2,213,279.

At April 30, 2019, the Company had approximately $37,500,000 of net operating loss carryforwards which will expire from 2033 to 2038. The Company believes its tax positions are all highly certain of being upheld upon examination. As such, the Company has not recorded a liability for unrecognized tax benefits. As of April 30, 2019, tax years 2015 through 2018 remain open for IRS audit. The Company has received no notice of audit from the Internal Revenue Service for any of the open tax years. Changes to the Federal Tax Code per the Tax Cuts and Jobs Acts that went into effect during the Fiscal Year ended April 30, 2018 are integrated into the tax rate calculation below. A reconciliation of income tax computed at the U.S. statutory rate to the effective income tax rate is as follows: