The Cost of Raising Children

The average middle income family with two children will spend $310,605 to raise a child born in 2015 up to age 17. The cost of raising a child is like Costco: You walk in, you got price per unit goes down in certain ways. So the more children you have, each subsequent child gets cheaper. And so the question is why do we have kids? Why do we even see it as a good thing?