GDP, unemployment, inflation. Trade, housing and stock market data. These are among the “leading indicators” that purport to define what matters in our economic lives. But these broad, clear-cut markers were developed decades ago, and gray areas have come to permeate the U.S. economy since those days. Nevertheless, these outmoded factoids still drive trillions of dollars in spending decisions and steer judgments about our success as a nation and as individuals.