It depends on your goals. If you want them to lay a lot of eggs, they need more feed as it takes a lot of calories to produce an egg a day. If you don't care about getting eggs, you can cut down on feed some and as long as they have enough to eat that they are not losing weight, they can maintain on less but won't have any reserves to produce many eggs.
I free feed mine - just keep the feeder full all the time - so I don't know what advice to give as far as measuring out quantities. I have found they only eat what they need and then move on. What I like about free feeding is that if there is a hen who is lower in the pecking order that gets chased away from the feeder by the more dominant hens, she still has a chance to go and eat when they are done. If I were measuring out a quantity of feed, I would worry that the dominant hens would keep the lower ranking hens away from the feeder until it was virtually empty, resulting in them not getting enough nutrition. It can be really hard to tell that a chicken is losing weight because the feathers conceal a lot and you have to pick them up to feel that they are skin and bone.
