When younger people enter the workforce and start planning for their future one thing they need to consider carefully is the cost of raising children.

When you start planning for your retirement and deciding how much you can afford to sock away in your 401(k), you'll need to understand the cost of raising children when you're putting your budget together.

According to a recent report from the USDA, "Expenditures on Children by Families," the average cost of raising a child today is over $245,000 — and that number doesn't include college tuition or inflation. Costs incurred after age 18 aren't tallied, including higher education. The USDA uses a 2.4% projected inflation rate to find that the inflation adjusted cost will be over $304,000 per child.

Those numbers are national averages, where you reside makes a fairly substantial difference in your child rearing costs. The most expensive region is the urban Northeast where the cost is $282,480 without an inflation adjustment. The urban South is less expensive at $230,610 and rural areas are much lower with the cost averaging $193,590.

The cost of housing is the largest expenditure when it comes to raising children. Regional differences in housing prices explain some of the variance we see in different parts of the country.

Child-care costs have risen over the years as most families have two working parents today and it is now the second largest expense. In 1960 child care was about 2% of the total cost and currently it's more like 18%. In 1960, the cost of raising a child was $25,230. It's risen almost tenfold today. Food is the third largest expense at about 16%.

The cost per child will decrease as you have more children. That makes sense since housing is the greatest expense. Kids can share rooms and items like clothes and toys can be handed down to younger children.

The USDA has the full report on their website, which includes a calculator that you can use to estimate your child rearing costs.

If you're a millennial doing some long-term planning, you'll need to decide how much you want saved at retirement and how much you can afford to contribute to your retirement account each year. You'll have to do some budgeting.

Knowing how much it will cost to raise your family the way you want to will help you make some of those important financial decisions today.