Why is the red line used to represent a stock that is clearly falling by 6 points on the K-line chart?
个股当天明明大跌6个点，K线图上为什么却用红线来表示？（中英）
I accidentally discovered this "bug" and initially thought that the stock software had made a mistake. Later, after studying the definitions of individual K-line charts in stock trading, I realized this knowledge about stocks. We all know that in the A-share market, rising stock prices are represented by red lines, while falling prices are represented by green lines. "Connecting the closing prices of stocks every day forms the trend chart of the stock."
我偶然发现了这个“bug", 还以为是股票软件弄错了。后来在学习了股票的单根K线图的相关定义后，才认识到这个股票的知识。我们都清楚，在A股市场，股价上涨，是用红线来表示，而下跌则用绿线，「每天的股票收盘价连起来就是股票的走势图」。
But why does the K-line chart use red (generally used to represent an increase) to represent a stock whose closing price clearly fell that day?
但为什么实际中出现了当天股票收盘价明明是下跌的，但是在K线图用了（一般用来表示上涨的）红色呢？
To answer this question, let's look at Figure 3 together and understand some concepts and drawing methods of positive and negative lines. The content of the illustration is very intuitive. The parts that both positive and negative lines have are the upper shadow line, lower shadow line, highest price, lowest price, etc. The solid portion between the opening price and closing price is the body of the positive or negative line.
要回答这个问题，我们一起来看图三，认识下阳线和阴线的一些概念和画法。图示内容很直观，阴阳线共同有的部分就是上影线、下影线和最高价、最低价等，阳线和阴线实体是开盘价和收盘价之间矩形部分。
It should be noted that the positions of the closing price and the opening price in the positive/negative lines are different. In a positive line representing a rising stock price, the opening price is below the rectangle, while the closing price is above the rectangle. In a negative line representing a falling stock price, the position of the opening and closing prices is opposite to that of a positive line.
需要注意的是，收盘价和开盘价的在阴线/阳线中所对应的位置是不同的——股价上涨的阳线，开盘价在矩形的下方，收盘价则在矩形的上方；股价下跌的阴线，开盘价与收盘价的位置则与阳线所对应的位置相反。
A single K-line chart represents the trend between the opening and closing prices of a stock for a specific day. Let's observe the stock price of "Longtou Stock" on October 17 in Figure 1. Although its price at the closing time, 8.10 yuan, dropped by 6.03% compared to the previous day's closing price, it is represented by a red K-line, which is usually used to represent an increase. The reason for this is that on October 17, its opening price was even lower at 8.06 yuan, so in terms of the trend, the closing price was higher than the opening price. Therefore, the K-line chart for that day used a red line, which indicates an increase.
某一天的单根K线图代表的是股价从开盘到收盘之间的趋势，我们观察图一“龙头股份”在10月17日的股价，虽然在收盘之时，它的价格8.10元较前一天收盘价跌了6.03%，但是它却用表示上涨的红色K线表示，其原因就在于在10月17日当天，它的开盘价更低，为8.06元，因此从趋势上来说，收盘是比开盘价高的，因此，当天的K线图就用了表示当天上涨的红色线来表示。
This is the stock knowledge I just learned. I hope it is useful for you. Thank you for reading~
这是我刚学到的股票知识，希望对你也有用。谢谢阅读～