After the stock price continues to fall, it generally becomes oversold. How to judge the oversold of the stock, everyone has different judgment methods. Different indicators show oversold in different ways, but no matter what indicators are, they are all combined with the current price and recent average price, forming a poor trend, which is the deviation rate we often hear. Deviation rate is an important indicator to judge oversold. In the software we use, BIAS is the deviation rate indicator. Deviation contains a wide range of contents, such as trend deviation, quantity deviation, current price deviation from average price, long and short deviation and so on. Far is near, long separation must be combined, long separation must be followed, and never give up. In the rise, the stock price is far from the moving average, which means that the deviation rate is too large and the stock price usually falls near the moving average. On the contrary, in the process of falling, if the stock price is far from the average price below the moving average, it is also oversold and the deviation rate is also large. At this time, the price will go up, which is the oversold rebound. Use the deviation indicator, which is usually set to 6-day deviation > +4.5%, which is a selling opportunity;