… is from page 120 of Diane Coyle’s 2014 book, GDP:
The constant improvements in the quality of products as well as the introduction of new goods and services over time have made it ever harder to calculate a meaningful general price level: today’s laptop is a vastly different machine from one bought just a few years ago for the same price, and the price of computing was infinite a few decades ago because computers did not exist. It is hard to capture this transformation in a single price index.
