Code of Virginia § 20-108.2 provides a guideline for determination of child support; quadrennial review by Child Support Guidelines Review Panel; executive summary.

C. (4) G. 3. Shared custody support.

(e) Support modification. When there has been an award of child support based on the shared custody formula and one parent consistently fails to exercise custody or visitation in accordance with the parent's custody share upon which the award was based, there shall be a rebuttable presumption that the support award should be modified.