(1) If the person proposing relocation of a child has substantially equal residential time:

(a) The presumption in RCW 26.09.520 does not apply; and

(b) In determining whether to restrict a parent's right to relocate with a child or in determining a modification of the court order as defined in RCW 26.09.410 based on the proposed relocation, the court shall make a determination in the best interests of the child considering the factors set forth in RCW 26.09.520.

(2) For the purposes of this section and RCW 26.09.430, "substantially equal residential time" includes arrangements in which forty-five percent or more of the child's residential time is spent with each parent. In determining the percentage, the court must (a) consider only time spent with parents and not any time ordered for nonparents under chapter 26.11 RCW; and (b) base its determination on the amount of time designated in the court order unless: (i) There has been an ongoing pattern of substantial deviation from the residential schedule; (ii) both parents have agreed to the deviation; and (iii) the deviation is not based on circumstances that are beyond either parent's ability to control.