An economic indicator is a measure of activity that affects the economy; it can be a ''leading economic Indicator" meaning it predicts/projects changes to the economy as a whole, a "lagging" one, that reflects larger changes already underway, or "coincident" ones that occur at the same time.
Economic Indicators are defined and tracked by different government agencies and non-governmental groups such as The Conference Board. which produces the "Leading Economic Index" and the "Consumer Confidence Index" (in conjunction with, and data from, Nielsen.)
They can cover the U.S., other individual countries, and global comparison data. Well known indicators are unemployement, interest rates, and Durable Goods Orders Report.
Data is collected and analyzed by various government agencies, but they often cross-list each other's information. Still, it may be useful to check the originating agency's site for the most detail.
