A. A court may modify a child support obligation upon a showing of material and substantial changes in circumstances subsequent to the adjudication of the pre-existing order. There shall be a presumption of material and substantial changes in circumstances if application of the child support guidelines in Section 40-4-11.1 NMSA 1978 would result in a deviation upward or downward of more than twenty percent of the existing child support obligation and the petition for modification is filed more than one year after the filing of the pre-existing order.
November 14, 1994, Filed
'We hold that parties may not, by private agreement, modify future child support obligations; rather, modification of future child support is a matter to be determined by the courts. See NMSA 1978 S 40-4-11.4 (Repl. Pamp. 1994)'
Paragraph 2, cites INGALLS v. INGALLS 1994