The Guaranteed Analysis shown on the information panel of a pet food package tells you how much crude protein, crude fat, fiber, and other vital nutrients are included in your pet's food. It is on an "as-fed" basis, meaning the values represent what is in the cat food straight from the bag or the can. This makes it difficult to compare values of dry food with those of canned, since the canned food has so much more moisture.
To best compare pet foods, it is wise to convert values to a dry matter basis - that is to compare the food nutrients after the water has been removed. The following charts show the protein, fat, and fiber levels for Drs. Foster and Smith cat foods on an as fed basis and on a dry matter basis :
Nutrients in Drs. Foster and Smith Cat Foods on a Dry Matter Basis