According to the USDA News (some of the text removed because it was more boring):
The Cost To Raise A Child:In March USDA released its annual report which details how much it costs to raise a child in America today. The report, titled "Expenditures on Children by Families" and released by USDA's Center for Nutrition Policy and Promotion, noted that for middle-income families with a child born in 2007, the costs of providing food, shelter, clothing, and other goods and services will total $204,060 by the child's 18th birthday.
"Since 1960, child-rearing expenses have changed noticeably," he added. Specifically, the cost of providing food decreased from 24 percent to 17 percent of total child-rearing costs, while child care and education expenses increased from 2 percent to 12 percent of total child-rearing costs. "For a middle-income, two-parent, two-child family," he said, "annual expenses for one child ranged from $10,930 to $12,030 depending on the age of the child, with expenditures on teenagers being the highest."