year in which the applicable qualifying child is born or adopted. (ii) Special rule In the case of a qualifying child who is adopted by the taxpayer and who is over the age of 5 on the date the adoption becomes final, the number of taxable years in the offset period shall be reduced by 1 year for each year by which the age attained by the qualifying child on the date the adoption becomes final is over the age of 5. (3) Election to claim credit on prior year return In the case of an applicable qualifying child born or adopted after the date that is 120 days after the date of the enactment of this subsection, a taxpayer may elect to treat such child as born or adopted on December 31 of the calendar year preceding such birth or adoption for purposes of this section. (4) Definitions For purposes of this subsection— (A) Applicable qualifying child The term applicable qualifying child means any qualifying child other than an eligible foster child (as defined in section 152(f)(1)(C)). (B) Applicable amount (i) In general The applicable amount is the amount, not to exceed the maximum credit amount, elected by the taxpayer. (ii) Maximum credit amount (I) In general The maximum credit amount is $5,000. (II) Special rule for certain adopted children In the case of a qualifying child who is adopted by the taxpayer and who is over the age of 5 on the date the adoption becomes final, the maximum credit amount shall be reduced by $500 for each year by which the age attained by the qualifying child on the date the adoption becomes final is over the age of 5. (C) Earned income amount The term earned income amount means the amount of earned income (within the meaning of section 32) which is taken into account in computing taxable income for the taxable year. For purposes of the preceding sentence, any amount excluded from gross income by reason of section 112 shall be treated as earned income which is taken into account in computing taxable income for the taxable year. (5) Special rule for certain low-income individuals (A) In