Ann: Australian Dairy Farms to acquire Camperdown Dairy Company, page-112

the understanding of milk prices seems to be poorly understood and models for incomes will be very flawed from what I read
water or milk may be a kilogram per litre but suppliers are not buying the 90+% of water they want the milk solids wish is small percent of that 1 kilogram of milk for 1 litre. good cows may produce 1 kilo ore more of solids a day
there may be a average "price on  litres" but milk is purchased $ per kg of protein and $ of butter fat. a cow may produce 30 litres of milk a day or 20 or 35 litres but there percentages will vary cow to cow how much percent of there milk is milk solids ( butter fat and protein) most of the milk is water don't forget.

so a farm with  lots of milk  may have 2 % milk solid or what ever percent so the price of the milk will vary with that.

start around page 30 http://www.mgc.com.au/media/24629/Supplier-Handbook-Southern-Milk-Region.pdf

as we have more then one herd of cows each herd will be different to some degree as well and seasonal depending on diets and water etc. it complex. and the cost of increasing milk solids butter fat and protein is not cheap and not quickly breeding with superior genetics is costly and slow improvements

the company should have some sort of fact sheet on this data for there milk quality for all share holders  to see, there is also thermodurics and bulk milk cell count ( bmcc) to take into consideration  in the price of milk and there is grades of milk from AA+ down to rejected milk as well .