average true range
- A measure of volatility used in technical analysis. The true range is the greatest of these three variables: (1) the current high minus the current low, (2) the absolute value of the current high minus the current low, (3) the absolute value of the current low minus the previous close. The average true range is a moving average of the true ranges over a given period (usually two weeks). The higher the ATR, the more volatile the price of an investment.