均幅指标（ATR）是取一定时间周期内的股价波动幅度的移动平均值，主要用于研判买卖时机。
均幅指标是显示市场变化率的指标，由威尔德（Welles Wilder）在《技术交易系统中的新概念》一书中首次提出，目前已成为众多指标经常引用的技术量。威尔德发现较高的ATR值常发生在市场底部，并伴随恐慌性抛盘。当其值较低时，则往往发生在合并以后的市场顶部。(The average amplitude index (ATR) is the moving average of the fluctuation range of the stock price in a certain period of time, which is mainly used to judge the timing of the sale.
Average index is the index to show the rate of market change. It is first proposed by Wilder (Welles Wilder) in the new concept of technology trading system. It has become the technology quantity cited by many indicators. Wilder found that higher ATR value occurs in the bottom of the market, and with panic selling. When the value is low, it often occurs at the top of the market after the merger.)