annual advance amount
(1) In general Except as otherwise provided in this subsection, the term “annual advance amount” means, with respect to any taxpayer for any calendar year, the amount (if any) which is estimated by the Secretary as being equal to 50 percent of the amount which would be treated as allowed under subpart C of part IV of subchapter A of chapter 1 by reason of section 24(i)(1) for the taxpayer’s taxable year beginning in such calendar year if— (A) the status of the taxpayer as a taxpayer described in section 24(i)(1) is determined with respect to the reference taxable year, (B) the taxpayer’s modified adjusted gross income for such taxable year is equal to the taxpayer’s modified adjusted gross income for the reference taxable year, (C) the only children of such taxpayer for such taxable year are qualifying children properly claimed on the taxpayer’s return of tax for the reference taxable year, and (D) the ages of such children (and the status of such children as qualifying children) are determined for such taxable year by taking into account the passage of time since the reference taxable year.