The Profit of a Mill
From the Domesday Book, A.D. 1086

Silton Manor -- "Two mills paying twelve shillings and a seven pence each"
Micheldever -- "A mill, which yields thirty pence"
Manningford -- "The mill yields twelve shillings and sixpence."
Pewsey -- "Seven mills yield four pounds and five shillings"

Domesday Book, Vol. I, p.23. A. Farley, Ed., Record Commission, London, 1783.
and
Domesday Book, trans. by Edward Edwards, Longmans, Green, Reader, and Dyer, London, 1866.