rj,
Herd is split pretty evenly, with regard to mature animals - about 35/group, though the fall-calving group in with the bulls has about 30 calves in addition to mature cows. I keep hay out in 6 rings and try to make sure that they all have hay in them, so that all animals have an adequate chance at getting their fill during their time in the hay-feedling lot. They average about one roll per day - though they don't always eat 'em all down at the same rate, so, for instance, this morning I had to put out 3 new rolls, as they'd cleaned up three of the six I put out on Sunday.
There's still some waste, but less than I experienced when they just stood around the hay rings all day long.
If I have time (most days) I'll usually go around the feeders with a pitchfork after each group and fork any loose hay back into the rings or pitch it over the fence to the wife's horses. Takes maybe five minutes or so.