By now numbers surround us. No important aspect of life is beyond their reach. This production of uniformity through numbers makes the world more readily administrable. The reduction of complex information to a few numbers, or even a single number, has become a common feature of contemporary life. In public statistics, the use of a single index number to summarize a broad and sometimes elusive concept has become overwhelmingly common.
Inflation is measured by indexes of consumer and of wholesale prices.
Trade balances, worker productivity, gross domestic product, the unemployment rate, and mean household income are other economic numbers used to assess the health of the American economy or the success of current economic policy. On the whole, understanding the role of numbers in the world has not been a high priority of mathematical education. Up to high school, mathematics generally means the manipulation of quantities and symbols. The problem of attaching numbers to the world is given rather little attention, except in relation to certain idealized problems chosen to promote a certain way of thinking rather than to learn about the world. Rarely do they learn what a stratified sample is, or how an unemployment rate is determined, or what the smog index measures.