Child support is a phrase that refers to the amount of money one parent pays to the other to help support their common-children when the parents are not living together. All child support calculations must start by using a formula. The Michigan Child Support Formula (MCSF) computes the child support obligation based upon net income which refers to gross income minus all of the deductions allowed for the purpose of calculating child support. The formula also adjusts for split custody arrangements or orders which provide for the children spending a substantial number of overnights in each parent’s home. All child support orders must provide for child support in monthly amounts.