I get asked the following question quite frequently: "How much food do I need to store for my family?" Well, the easy answer is that it depends on the size/ages, etc. of those in your family. However, a more specific plan can be generated by a good Food Storage Calculator, such as the one linked above. I don't know a lot about the web site, which is obviously trying to sell products in addition to providing the Calculator, but as a useful tool for figuring out how much food you need to stock it could be a good resource.