In 1780, Massachusetts enacted what may be the first documented case of formal price indexation. ... [F]acing a crisis in maintaining Revolutionary War enlistments at a time when the value of the currency was unstable and falling, they hit upon a scheme to use indexed interest-bearing notes as payment. Both principal and interest on these ‘‘depreciation notes’’ were to be paid not at their nominal values but ‘‘in the then current Money of the State, in a greater or less Sum, according as Five Bushels of Corn, Sixty-eight Pounds and four-seventh Parts of a Pound of Beef, Ten Pounds of Sheeps Wool, and Sixteen Pounds of Sole Leather shall then cost, more or less than One Hundred and Thirty Pounds of Current Money.’’ Pursuant to the Massachusetts act, county agents were named and charged with collecting average price data every month.There is apparently some historical question as to whether this price index was calculated accurately and honestly, but I love the example nonetheless. The idea of price indexes was apparently in the air around this time. Persky writes: "An Italian named G. R. Carli is often credited with having developed the first price index number. In work published about a decade before The Wealth of Nations, Carli made a serious empirical investigation of prices over time, including a simple average of the percentage changes in three commodities—grain, wine and oil—over the period 1500 to 1750."