Typically the term is used to denote the change in a security’s listed price on a stock exchange from the time the exchange opens at the start of its trading day until the exchange closes at the close of its trading day.
A full trading day begins when Asian exchanges open and ends when American exchanges close. So in a broader sense of the term, the price change in an asset’s market rate is the difference between its opening price on Asian exchanges and its closing price on North American exchanges.
Although not typically accounted for because its effects are not noticed until exchanges open, pre-hours trading and after-hours trading also impact daily price change.
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