The Minnesota child support statute changed significantly in 2007. If you were divorced before 2007 and paying child support, your obligation is likely calculated under the “old" system. If you were divorced after 2007, you are operating under the new system. The new law completely overhauled how child support is calculated. Under the old law, the key element was which parent had physical custody. The parent with physical custody was owed child support by the other parent. Now support is calculated based on a combination of both parents incomes as well as parenting time.
The new child support law looks at the gross (before tax) monthly income of both parents. If you are the parent with less parenting time or the parent with more income in situations of almost equal parenting time, you contribute your share by paying support to the other parent. To calculate the amount of support, the legislature created a formula that first calculates how much it "costs" to care for X number of children if both parents earn a total of Y dollars. Each parent is obligated to contribute their proportional share of this "cost." If, for example, you make 60% of the total gross income, you are obligated to contribute 60% of the "cost." which is called the basic support obligation. This basic support obligation is reduced by the percentage of parenting time. If you have less than 10% parenting time, you do not get a reduction. For parenting time between 10-45% you get a small reduction and if you effectively share parenting time equally (between 45.1% and 50%) you are entitled to an even greater reduction. There are also other factors that increase or decrease the obligation: imputed income, receipt or payment of spousal maintenance, non-joint children, and veteran's benefits to name a few.
In addition to the basic support obligation addressed above, Minnesota's child support statute requires both parents contribute towards work related child care expenses, medical premiums and out of pocket medical costs. You are obligated for the percentage of these costs that is equal to your percentage of the total gross income. Same as my example above, if you earn 60% of the gross income you are obligated to pay for 60% of these expenses There is no parenting time "discount" for these amounts.
Sounds complicated? It is. And frankly, I never do the calculations by hand. There is a child support calculator available here. The calculator takes care of all the hard work so long as you plug in the right information which can be difficult without attorney assistance. Parties can argue for a deviation from the calculated guidelines based on the fact that a lower or higher amount of support in if they can the child or children's best interests. But, this is somewhat difficult to do. That makes child support one area of law where if you know a few key facts you can somewhat quickly determine what a court would order.