17. SARPA recalculates child support taking into account the expenses granted by the court for the child or, if more recent, the expenses taken into account by SARPA at the last recalculation. However, if there is an agreement between the parents to change the amount of the expenses or if the amount of the expenses must be changed because of the withdrawal, addition or modification of an advantage, subsidy, deduction or tax credit having an impact on the expenses, SARPA adjusts the child support taking into account the amount of the expenses as agreed on by the parents or as changed.
SARPA also recalculates the child support for a child taking into account the custody time granted by the court to each parent or, if more recent, the custody time taken into account by SARPA at the last recalculation. However, if there is an agreement between the parents to change the custody time, SARPA recalculates the child support taking into account the custody time agreed on by the parents, provided that the agreement between the parents does not change the type of custody and that the determination or last change of custody time is based on an agreement between the parents that was the subject of a judgment or that was taken into account by SARPA at the last recalculation following such a judgment.