Gerald,
I feed my 20 pounder about 6.5-7 ounces per day. My ~100 pounder gets around 19-20 ounces. As you can see per pound, my larger dog gets much less, but she did have a serious issue being overweight before this diet and I've just kept it up. Sometimes they get much less as I give them a large bone that they usually strip it of the meat and fat and are unable to break the bone into smaller pieces, in these cases they end up getting only a fraction of their usual amount, but spend several hours gnawing at the bones and are usually tired afterwards.
There is a pdf file I have that talks about the appropriate amount. I'll find it and email it to you. I know this may seem anal, but I do weigh their food using a postal digital weight machine
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