G.D.P. is an index of a country's entire economic output - a tally of, among many other things, manufacturers' shipments, farmers' harvests, retail sales and construction spending. It's a figure that compresses the immensity of a national economy into a single data point of surpassing density. The conventional feeling about G.D.P. is that the more it grows, the better a country and its citizens are doing. [But] it has been a difficult few years for G.D.P. For decades, academics and gadflies have been critical of the measure, suggesting that it is an inaccurate and misleading gauge of prosperity. What has changed more recently is that G.D.P. has been actively challenged by a variety of world leaders, especially in Europe, as well as by a number of international groups, like the Organization for Economic Cooperation and Development. The G.D.P. ... has not only failed to capture the well-being of a 21st-century society but has also skewed global political objectives toward the single-minded pursuit of economic growth. Which indicators are the most suitable replacements for, or most suitable enhancements to, G.D.P. Should they measure educational attainment or employment? Should they account for carbon emissions or happiness?