What group can claim credit for being the driving force behind the world’s largest economy? Hint: You are probably a member of this group.

The answer is U.S. consumers, whose spending is responsible for more than 70% of U.S. gross domestic product (GDP). As we’ve seen in recent years, when consumer conditions are bad, the effects can be widespread. If consumer spending falters, it affects business income and tax revenues. If revenues fall far enough, the effects can include increased unemployment, which in turn exaggerates the problem because the unemployed have reduced incomes and tend to make fewer purchases.

Economists, traders, investors, and policymakers all take great interest in the financial health of consumers and what they may do next. Here are some popular indicators of consumer behavior.

The Monthly Retail Trade Survey is conducted by the U.S. Census Bureau, which mails questionnaires to about 12,500 businesses. The Census Bureau uses the data

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