King and Davenant

Playing with figures fascinated Gregory King. His notebooks bulge with calculations about the chief economic and demographic preoccupations of the day. Nothing King wrote was published until long after his death, but some of his estimates and speculations were published by Charles Davenant (who repeatedly made clear the extent of his debt to King). Given the nature of pre-industrial society, it was to be expected that one of the topics that would attract King's attention was the scale of agricultural production and the price of the foodstuffs produced.

It had long been high in the consciousness of men and of governments that when the harvest failed the price of food was affected disproportionately and Davenant attempted to set out the relationship quantitatively. How far Davenant's discussion of this issue was directly his own work and how much it was a summary of King is unclear, but his analysis has been immensely influential and it is convenient to refer to the ‘model’ under Davenant's name. He specified the degree to which price was increased by harvests which were successive deciles below the average. His estimates were widely quoted and broadly confirmed by a number of later examinations of the same issue. Jevons, for example, accepted the general accuracy of the formula which Davenant published and sought an expression which would generalise the relationship between quantity and price.