Del. Fam. Ct. Civ. R. 505

(a) Gross obligation. Each parent’s Gross Obligation is the sum of the individual’s Primary

Support Obligation (Rule 503(b)) and Standard of Living Adjustment (Rule 504).

(b) Credits. Each parent shall retain from their Gross Obligation:

(1) Primary Support Allowance for the children of this union in their primary or shared

placement; and

(2) Child care, private school, or other primary expenses claimed by the parent as allowed by

Rule 503(b) or (c); and

(3) Per capita share of the parents’ combined SOLA obligation for the children of this union

in each parent’s primary or shared placement; and

(4) Parenting Time Adjustment as set forth in Rule 505(c), if applicable.

(c) Parenting time adjustment. When a child spends an average of more than 79 but less than 164

annual overnights in the household of the parent from whom support is sought, that parent

shall be entitled to retain a percentage of the primary support allowance allocable to that

child and combined SOLA and shall be known as the Parenting Time Adjustment. The

percentage is 10% for 80 to 124 overnights, and 30% for 125 to 163 overnights.

Additionally:

(1) The number of overnights must be proven by court order, written agreement, previous

finding, or other clear and convincing evidence. The party asserting a number of

overnights other than as indicated in the order, agreement, or previous finding carries the

burden of proof.

(2) Modest or temporary departures from the established contact schedule will not prompt

any adjustments or rebuttal of the Formula.

(3) Where the residential arrangement is complex with children in different ranges, then the

percentages should be averaged.