The fluctuation range is to limit the fluctuation range of the stock price. The range of stock price changes in a day to prevent the stock from skyrocketing and plunging, causing market chaos. Only transactions within the upper and lower limits of this range can be allowed to enter the stock market, and commissions beyond this fluctuation range will not be borne. The extent of the rise and fall depends on the closing price of the stock the day before. Those who rise to the upper limit are called "upper limit high price" and those who fall to the lower limit are called "lower limit low price".
It can be seen that the fluctuation range is not only different in different stock markets, but also changes with time in the same market. Generally speaking, the fluctuation range depends on the stock market and the political and economic situation behind it. Often in the era of great changes, the ups and downs are too big to control, either the excessive false prosperity of the market or the collapse of the stock market. In both cases, the fluctuation range is actually uncontrollable and uncertain, which is far from the optimal level.
In the stock market and futures trading market, the expression of ups and downs is useful, and the expression of ups and downs is different in different countries. Western countries usually use green for rising and red for falling. In China, red stands for rising and green stands for falling.
Point-line-surface representation refers to a linear graph that connects the average price points of stock prices or futures prices in a certain unit time in each trading day, thus showing the price change state in the corresponding trading day, that is, the fluctuation range, so that traders can see at a glance.
Candle graphic method candle graphic method is what we usually call k-line graphic method, also called yin-yang line The data used in candle chart method are drawn at the opening price, closing price, highest price and lowest price per unit time. In the figure, China shows the rising interval in red and the falling interval in green, which is the same as the red and green data. The longer the candle chart, the greater the fluctuation.