Because the federal, state and local taxing authorities require taxes to be paid at least quarterly during the year, it is often imperative to recalculate estimated tax obligations during the tax year in order to meet the estimated tax requirements. We often perform preliminary tax analysis of tax obligations for our clients just prior to the end of the year in order to make the necessary adjustments that, if not made, would result in clients incurring penalties for underpayment of estimated tax liabilities.