here is the link for the Federal Child Support Guidelines. they have a break down by state.
http://www.acf.dhhs.gov/programs/cse/fct/sp96_ar.htm
and here is the link for the Arkansas
http://www.arkleg.state.ar.us/newsdcode/lpext.dll?f=templates&fn=main-hit-h.htm&2.0
<b> this is what was available on line, you need to double check with the contact names from the first link (listed at the bottom) and make sure that it is the latest and greatest and still applies. </b>
9-14-237. Expiration of child support obligation.
(a)(1) An obligor's duty to pay child support for a child shall automatically terminate by operation of law when the child reaches eighteen (18) years of age or should have graduated from high school, whichever is later, or when the child is emancipated by a court of competent jurisdiction, marries, or dies, unless the court order for child support specifically extends child support after such circumstances.
(2) Provided, however, that any unpaid child support obligations owed under a judgment or in arrearage pursuant to a child support order shall be satisfied pursuant to § 9-14-235.
(b)(1) If the obligor has additional child support obligations after the duty to pay support for a child terminates, then either the obligor, custodial parent, physical custodian, or the Office of Child Support Enforcement may, within thirty (30) days subsequent to the expiration of the ten-day period allowed for the notification, as provided in subdivision (b)(5) of this section, file a motion with a court of competent jurisdiction requesting that the court determine the amount of the child support obligation for the remaining children.
(2) The remaining obligations, subsequent to the expiration of the thirty-day period contained in subdivision (b)(1) of this section, shall be adjusted by operation of law to an amount to be determined by using the most recent version of the family support chart pursuant to § 9-12-312(a)(2) for any remaining children for whom an obligation for child support exists.
(3) If the most recent child support order either was entered prior to the adoption of the family support chart by the Arkansas Supreme Court or the support amount, as indicated by the order, deviated from the family support chart, then the issue of the amount of the obligor's child support obligation shall be decided by a court of competent jurisdiction.
(4)(A) In the event a review is requested, the court shall apply the family support chart for the remaining number of children from the date of the termination of the duty, subject to any changed circumstances, which shall be noted in writing by the court.
(B) Deviation from the family support chart shall be noted in the court order or on the record, as appropriate.
(5)(A) The obligor shall provide written notification of the termination of the duty of support to the custodial parent, physical custodian, the clerk of the court responsible for receipt of the child support payments, the obligor's employer, if income withholding is in effect, and the Office of Child Support Enforcement, if applicable, within ten (10) days of the termination of the duty of support.
(B) The obligor shall enclose with the written notification of termination a copy of the most recent child support order.
(C) The notification shall state the name and age of each child for whom the obligation to pay child support has ceased and the name and age of children set out in prior terminations of child support made pursuant to this subsection.
(c) No statute of limitations shall apply to an action brought for the collection of a child support obligation of arrearage against any party who leaves or remains outside the State of Arkansas with the purpose to avoid the payment of child support.