USDA: Official Cost of Food at Four Levels

Food budgeting for us is a challenge.  Our budget currently is $60 dollars a week.  We go over frequently, but rarely more than $5-10 dollars.  It's a good goal for us, and lately we've been fantastic at meeting it.

The United States Department of Agriculture (USDA)  and the Center for Nutrition Policy and Promotion issued a table presenting the average weekly and monthly cost Age/Genger groups and Families of 2 and 4 and their correlating average cost of food at four levels Thrifty Plan, Low Cost Plan, Moderate Cost Plan, and Liberal Cost Plan.  

"To calculate overall household food costs, (1) adjust food costs for each person in
household and then (2) sum these adjusted food costs."
Accordingly, the weekly average of food on the Thrifty Plan for my family
((Family (M&F) of 2, 19-50 years) 87.30 + (individual child of 2-3 years) 23.5) + .5%(total)= $116.34

Ok that was super confusing.  Essentially, using USDA's equation my family should be spending $116.34 on average per week and this is based on their studies of healthy eating.  "The Food Plans represent a nutritious diet at four different cost levels" (USDA).
DID YOU READ THAT?!!! I'M INCREDIBLE!   I manage to feed my family in a healthy way $56.34 less than the average, healthy, expected weekly amount.  AND THAT WAS THE THRIFTY PLAN!!! How?  Simple! I don't buy junk food, I plan for my meals, buy off brands, and if able plan my meals around what is on sale.