All of these examples show how futile and reductive it is to try to sum up all these changes with a single index, as in “the standard of living increased tenfold between date A and date B.” When family budgets and lifestyles change so radically and purchasing power varies so much from one good to another, it makes little sense to take averages, because the result depends heavily on the weights and measures of quality one chooses, and these are fairly uncertain, especially when one is attempting comparisons across several centuries.
