Note 9—Income Taxes 

We recognize deferred tax assets and liabilities, at enacted income tax rates, based on the temporary differences between the financial reporting basis and the tax basis of our assets and liabilities. We include any effects of changes in income tax rates or tax laws in the provision for income taxes in the period of enactment. When it is more likely than not that a portion or all of the deferred tax asset will not be realized in the future, we provide a corresponding valuation allowance against the deferred tax asset.

Our sources of income (loss) and income tax provision (benefit) are as follows (in thousands):

The difference between the tax provision at the statutory federal income tax rate and the tax provision attributable to income (loss) from continuing operations before income taxes is as follows (in thousands):

We recorded income tax expense of $3.9 million and income tax benefit of $1.3 million for the years ended December 31, 2020 and 2019, respectively, a $2.7 million increase in income tax expense.

We do not expect to repatriate earnings from its foreign subsidiaries because the cumulative earnings and profits of the foreign subsidiaries as of December 31, 2020 and 2019 are negative. Accordingly, no U.S. federal or state income taxes have been provided thereon.

Deferred income tax assets and liabilities reflect the net tax effects of (i) temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts for income tax purposes and (ii) operating loss carryforwards. The tax effects of significant components of our deferred tax assets and liabilities are as follows (in thousands):

We have retained a full valuation allowances of $3.6 million against the deferred tax assets of our Australian, Canadian, U.K., Hong Kong, and South Africa subsidiaries as of December 31, 2020. We have retained full valuation allowances of $4.7 million against the deferred tax assets of our United States, Australian, Canadian, U.K. (excluding Elite Legacy Education UK), Hong Kong, and South Africa subsidiaries as of December 31, 2019. The most significant negative factor that was considered in determining whether a valuation allowance was required is a cumulative recent history of losses in all jurisdictions for the entities mentioned above.

We had zero balance of federal net operating loss carryforwards as of December 31, 2020. As of December 31, 2019, we had approximately $4.8 million of federal net operating loss carryforwards. As of December 31, 2020, and 2019, we had approximately $16.5 million and $19.7 million of foreign net operating loss carryforwards, respectively, and approximately $0.3 million and $8.9 million of state net operating loss carryforwards, respectively. The foreign loss carryforwards begin to expire in 2027 and the state net operating loss carryforwards begin to expire in 2038.

Our federal income tax returns for the years after 2017 are subject to examination by the Internal Revenue Service. Our state tax returns for all years after 2017 or 2016, depending on each state's jurisdiction, are subject to examination. In addition, our Canadian tax returns and United Kingdom tax returns for all years after 2013 are subject to examination.

The liability pertaining to uncertain tax positions was $0.3 million at December 31, 2020 and 2019. In accordance with GAAP, we recorded expense that increased the total liability pertaining to uncertain tax positions which was more than offset by a decrease in the total liability attributable to foreign currency fluctuations and tax rate adjustments. A significant portion of the liability pertaining to uncertain tax positions is recorded as a reduction of the value of net operating loss carryovers.

We include interest and penalties in the liability for uncertain tax positions. Accrued interest and penalties on uncertain tax positions were approximately $0.04 million at December 31, 2020 and 2019, for each year, and is included in other liabilities in the accompanying Consolidated Balance Sheets. If applicable, we recognize interest and penalties related to uncertain tax positions as tax expense.

The following is a tabular reconciliation of the total amounts of unrecognized tax benefits:

The total liability for unrecognized tax benefits at December 31, 2019, is netted against deferred tax assets related to net operating loss carryforwards in the Consolidated Balance Sheets. The total liability for unrecognized tax benefits at December 31, 2020 and 2019, are as follows:

We do not expect any significant changes to unrecognized tax benefits in the next year. We estimate $0.3 million of the unrecognized tax benefits, if recognized, would impact the effective tax rate at December 31, 2020 and 2019.