Well, the website listed only reports crude protein. Again, protein is only as good as the limiting amino acid.
Formulating your own feed is much more difficult that most think. First, you have to know what the hen actually needs, not just % protein, but amino acids, and amino acid ratios, essential fatty acids, minerals, and vitamens. Second, you need to know all these variable about all possible feeds you have access to. Next, you have to balance them (generally realted to the ME content of the feed because that will control how much they eat). Next, you need to calculate the percentages. Feed mills tend to use a least-cost linear programming method that uses all the feedstuffs available to them, their nutritional content, and costs to develop the least-cost diet.
If you believe you can do a better job, go for it, but DO NOT expect it to be cheaper....and probably not better. Unless you have a specific customer audience (i.e. no soy, no who cares), you will not make a better, cheaper diet.
Clint