William Index (WMS% or R%) was first created by Larry William in 973 and was originally used in the futures market. WMS% indicates whether the market is overbought or oversold. The calculation formula and physical meaning of 1.wms%. Wms% = (Cn-ln)/(HN-ln) *100% on n days, where cn is the closing price of the day; Hn and Ln are the highest and lowest prices in recent days (including today). According to the formula, WMS% has one parameter, that is, the selected days N0. WMS% refers to the relative position of the closing price of the day in the whole price range in the past period of time. If the value of WMS%% is relatively large and the price of the day is in a relatively high position, be careful not to fall back; If the value of WMS% is small, it means that the price of the day is relatively low, so beware of rebound; The value of WMS% is in the middle, about 50%, so the price of that day may fluctuate up and down. WMS% indicator can be understood in this way. A moving ball jumps up and down in a space with a ceiling at the top and a floor at the bottom. When the ball hits the ceiling up, it will turn down, and when it hits the floor of the factory, it will bounce. The external force of the ball moving up and down is zero, so the ball will move up and down regularly and continue. However, due to the constant changes in the strength of both sides, the external force on the ball is not zero. Many forces are strong, and the ball moves upward; When the air force is large, the ball moves down. But the U-turn after hitting the ceiling and floor is always correct, just not as regular as when there is no external force. If you hit it, you won't look back. You may have to hit it several times before you look back. This is because of external forces. 2. Parameter selection and application rules of WMS%. The ceiling and floor mentioned above are constantly changing with time, which is the problem of parameter selection. In the early days of WMS%, people thought that a market cycle was about four weeks, so taking the first half or the second half of this cycle must contain the highest or lowest point of this cycle. In this way, as long as the parameter selected by WMS% is 2 weeks, at least one of Hn or Ln will become the ceiling or floor in these 2 weeks. This is very helpful for us to use WMS% to open up the market. For the above reasons, the selection parameter of WMS% should be half of the-period. At present, there is no clear result about the cycle of China stock market. When we apply WMS%, we always try to choose more parameters. The operation rules of WMS% are also considered from two aspects: one is to take the absolute value from WMS%; The second is from the shape of WMS% curve. (1) Consider the absolute value of WMS%. The value of WMS% in the formula is between 0% and 100%, and it is divided into upper and lower regions with 50% as the central axis. 1) When WMS% is higher than 80%, it is overbought and the market is about to peak, so we should consider selling. 2) When WMS% is less than 20%, it is oversold, and the market is about to bottom out, so we should consider buying. Here, 80% and 20% are only empirical figures, not absolute. Some stocks may require more than 80% or less. Different situations produce different buying lines and throwing lines, and we should constantly explore them in actual combat according to specific conditions. It should be noted that in China and Shanghai markets, the buying line is generally lower than 20%, and the selling line is generally higher than 80%. (2) Consider the curve shape of WMS%. Only the deviation principle and the principle of hitting the top and hitting the bottom are introduced here. 1) After WMS% enters the high position, it is generally necessary to turn back. If the stock price continues to rise at this time, it will lead to deviation, which is a signal of shipment. 2) After 2)WMS% enters the low level, it will generally rebound. If the stock price continues to fall at this time, it will deviate and be a signal to buy. 3)WMS% touches the top (bottom) several times in a row, and some of them form double or multiple (bottom), which is the signal of shipment (buying). There are still some things that can be introduced from the shape of WMS%, which are left in the following indicators.