There are so many variables to consider - are you in a long day care setting providing breakfast, lunch, morning/afternoon tea and late snack…or a preschool providing only 3 meals a day? Does your service cater for babies as well as older children; if including babies in your calculations, it may reduce your average costs per child as babies do not eat that much and families may provide formula for really young ones.
There have been surveys carried out showing some services spend as little as 65 cents a day per child, whilst others spend around $4. I am sure you can guess which service I would rather eat at!
What one centre spends will not always compare to your own situation. You need to make sure you are catering to the children’s nutritional needs and there is plenty of food available so no child misses out. If budget is an issue maybe consider using more seasonal produce to keep costs down for example. Hope that helps.