The stock market is not by luck. Only by deeply understanding the market, understanding the laws of the stock market and constantly summing up and learning can we survive for a long time. I hope everyone can form their own trading system. Here, I want to share some information about the stock index for your reference.
share index
The stock index is the stock price index. It is a reference index compiled by stock exchanges or financial services institutions to indicate changes in the stock market. Due to the volatility of stock prices, investors are bound to face market price risks. It is easy for investors to know the price changes of a specific stock, but it is neither easy nor annoying to know the price changes of various stocks one by one. In order to adapt to this situation and need, some financial service institutions make use of their professional knowledge and the advantages of being familiar with the market to compile stock price indexes and publish them publicly as indicators of market price changes. Based on this, investors can test the effect of their investment and predict the trend of the stock market. At the same time, the press, company bosses and even political leaders also use this as a reference index to observe and predict the social, political and economic development situation.
This stock index, that is, the average price indicating the changes in the stock market. A stock index is usually compiled based on a certain month of a year, and the stock price in this base period is 100. The stock prices in subsequent periods are compared with the base period price, and the percentage of rise and fall is calculated, which is the stock index of this period. Investors can judge the trend of stock price according to the rise and fall of the index. And in order to reflect the trend of the stock market to investors in real time, almost all stock markets will announce the stock price index at the same time as the stock price changes.
There are three factors to be considered in calculating the stock index: first, sampling, that is, extracting a few representative constituent stocks from many stocks; The second is weighted, weighted average by unit price or total value, or unweighted average; The third is a calculation program, which calculates arithmetic average, geometric average, or considers price and total value.
Because there are many kinds of listed stocks, it is an arduous and complicated task to calculate the average price or index of all listed stocks, so people often choose a few representative sample stocks from listed stocks and calculate the average price or index of these sample stocks. Used to indicate the general trend and fluctuation range of stock prices in the whole market. When calculating the average or index of stock price, the following four points are often considered: (1) sample stocks must be typical and common. Therefore, the factors such as industry distribution, market influence, stock grade and appropriate quantity should be considered comprehensively when selecting sample correspondence. (2) The calculation method should have high adaptability, and can make corresponding adjustments or corrections to the rapidly changing stock market, so that the stock index or average value has good sensitivity. (3) There should be scientific calculation basis and means. The calculation basis must be unified, generally based on the closing price, but with the increase of calculation frequency, some are calculated at the hourly price or even shorter time. (4) The base period should be well balanced and representative.
Comprehensive question and answer of stock index
1, what is a stock index?
The stock price index is compiled by using the index method in statistics, which reflects the changes and trends of the overall price of the stock market or a stock price.
According to the range of stock price index reflecting price trend, stock price index is generally divided into component index, comprehensive index and classification index. Component index can not only reflect the overall trend of the market, but also be used as a yardstick to measure investment performance. As a benchmark portfolio of a market, it reflects the basic income of the market, is investable, and can generally be used as the target of index funds.
2. Why do you want to compile a stock index?
Due to the influence of political, economic, market and psychological factors, the price of each stock is constantly changing, and there are many stocks trading in the market all the time. In order to judge and grasp the price change level and trend of the whole stock market from the complicated price changes of many stocks, Charles, one of the founders of Dow Jones Company, USA. Henry. Tao was the first person to find a measurement method with paper and pen! This is the famous Dow Jones average stock price index.
Now the stock markets all over the world have their own stock index. In addition to the Dow Jones index, there are the S&P stock index in the United States, the Financial Times stock index in London, the Nikkei index in Japan and the Hang Seng index in Hong Kong, all of which are constituent stock indexes.
The stock price index is generally compiled and published by stock exchanges, financial service institutions, consulting and research institutions or news organizations.
3. What is the basic function of the stock index?
Stock price index is produced in securities trading activities. It is not only an important indicator to reflect the changes in the stock market, but also a reference indicator to observe the economic situation and cycle. It is regarded as the "wind vane" of the stock market and the "barometer" of economic prosperity changes. The stock price index has the following basic functions:
(1) comprehensively reflects the changing direction and degree of stock prices in a certain securities market in a certain period.
(2) Provide information for investors and analysts to study and judge the dynamics of the stock market, and facilitate the analysis of the general trend of the stock market.
(3) As a yardstick for evaluating investment performance, it provides "benchmark return" for stock market investment.
(four) as the basis of index derivatives and other financial innovations.
4. What indexes does SSE have now?
At present, the stock index series of Shanghai Stock Exchange includes four categories and ten indexes:
(1) component index: SSE 180 index;
(2) Comprehensive index: Shanghai Composite Index;
(3) Classification indexes: Shanghai A-share index, Shanghai B-share index, Shanghai industrial index, Shanghai commercial index, Shanghai real estate index, Shanghai public utilities index and Shanghai comprehensive industrial index.
(4) Fund Index: Shanghai Stock Exchange Fund Index.
5. Why should the SSE 180 index be compiled?
In June 2002, Shanghai Stock Exchange adjusted the original SSE 30 Index and renamed it SSE Component Index (referred to as SSE 180 Index). According to the development of China's stock market and international experience, the compilation scheme of Shanghai Stock Exchange Component Index is further improved on the basis of the original compilation scheme of Shanghai Stock Exchange 30 Index. The purpose is to select the most representative sample stocks through scientific and objective methods, and to establish a benchmark index reflecting the overall situation and operation of the Shanghai stock market, which can be used as the basis for investment evaluation and financial derivatives. The launch of Shanghai Stock Exchange 180 index is an important measure for Shanghai Stock Exchange to promote market construction, improve service level and improve market functions.
6. What is the market function and significance of the newly compiled SSE 180 index?
The launch of SSE 180 index is an important event in the construction of China stock market, which is of positive significance for promoting the standardized development of the market.
(a) is conducive to the development of institutional investors, improve the main structure of market investment.
The introduction of SSE 180 index can not only provide authoritative investment direction and good tracking targets for all kinds of institutional investors, but also reduce their operating costs, and provide more objective standards for all parties in the market to evaluate the performance of institutional investors such as investment funds, which is conducive to expanding the ranks of institutional investors, optimizing the investment subject structure of the market and attracting more large funds to enter the market.
(2) It is conducive to guiding rational investment and promoting the development of market norms.
The Shanghai Stock Exchange 180 index is compiled by the international mainstream method, and the selection of sample stocks represents the market value orientation, which helps to guide investors to establish a correct investment concept and increase market activity to some extent. Institutional investors' attention and investment in sample stocks is more conducive to promoting the healthy development of the market.
(3) It is beneficial for market participants to understand and evaluate the market more objectively.
Because the composite index contains all the stocks in the market, there are many defects in reflecting the market situation, and the major markets in the world generally adopt component indexes to reflect the market development. The launch of SSE 180 index is based on such market demand, which helps market participants to know and evaluate the market more accurately.
7. What's the difference between Shanghai Stock Exchange 180 index and some existing Shanghai stock exchange indexes?
(1) The selection range of sample stocks is different.
Stocks included in the index calculation range are called sample stocks. The SSE 180 index is a constituent stock index, and some representative sample stocks are selected from all A-share stocks listed on the Shanghai Stock Exchange to be included in the index calculation. So it is different from the existing Shanghai Composite Index, which is the price index of all listed stocks. It is also different from various sub-indices, whose sample stocks are all stocks in the corresponding stock category or industry category.
(2) The calculation method of weight is different.
Unlike the previous indexes weighted by total equity (such as Shanghai Composite Index and Shanghai Sub-index) or circulating equity (such as Shanghai 30 Index), the "Shanghai Stock Exchange 180 Index" is graded and weighted.
8. How many samples does the SSE 180 index contain? What are the selection criteria for the constituent stocks of SSE 180 index?
The SSE 180 index contains 180 samples.
Industry representativeness, scale and liquidity are the most basic and core standards for index sampling at home and abroad. Industry representativeness reflects the national economic structure and aims to meet the needs of investment management; Scale can ensure the representativeness of indicators; Liquidity can ensure the tradeability of the index. The sampling standard of SSE 180 index also follows three indicators: scale (total market value and circulating market value), liquidity (transaction amount and turnover rate) and industry representativeness, that is, stocks with large scale, good liquidity and strong industry representativeness are selected as samples.
9. How is the SSE 180 index compiled (compilation principle)?
(1) Determine the sample space.
All Shanghai A shares excluding the following stocks:
(a) shares listed for less than a quarter;
(2) Suspension of stock listing.
(3) stocks with abnormal operating conditions or serious losses in recent financial reports;
(four) the stock price fluctuates greatly and the market performance is obviously manipulated;
5] Other stocks that should be eliminated as determined by the expert committee.
(2) Select sample stocks.
(a) according to the total market value, circulation market value, transaction amount, turnover rate of the stock comprehensive ranking;
(2) Only a few samples are distributed according to the proportion of market value of each industry;
(3) According to the distribution of industry samples, select the top stocks in the industry;
(4) Further adjust the samples selected by various industries to make the total number of constituent stocks 180.
(3) Regular adjustment of sample stocks.
Based on the principle of combining sample stability with dynamic tracking, the Shanghai Composite Index is adjusted once every six months, and the proportion of each adjustment is generally not more than 10%. Under special circumstances, the sample can be temporarily adjusted.
How are the 10 and Shanghai Stock Exchange 180 indices calculated?
The component index of Shanghai Stock Exchange is calculated by the licensed weighted comprehensive price index formula, with the adjusted share capital of sample shares as the weight.
Index of the reporting period = (adjusted market value of constituent stocks in the reporting period ÷ adjusted market value of constituent stocks on the benchmark date) × 1000.
Among them, the adjusted market value = ∑ (market price × adjusted share capital), and the adjusted market value of constituent stocks on the base date is also called divisor, and the adjusted share capital adjusts the share capital of constituent stocks by grading. According to the international practice and the opinions of the expert committee, the classification method of the component index of Shanghai Stock Exchange is shown in the following table. For example, if the proportion of tradable shares (circulating share capital/total share capital) of a stock is 7% and less than 10%, the circulating share capital will be the weight; The circulation ratio of a stock is 35%, which falls at 30,40? The corresponding weight ratio is 40%, with 40% of the total share capital as the weight.
1 1 and when will the Shanghai Stock Exchange 180 index be released? How is the base point determined?
The SSE 180 index is a continuation of the SSE 30 index officially released on July 1 96 and July 1 2002. The base point is the closing point of Shanghai Stock Exchange 30 Index on June 28th, 2002.
Calculation method of stock index
Calculation method of stock index When calculating the stock index, the stock index and the average stock price are often calculated separately. By definition, the stock index is the average share price. However, as far as their actual impact on the stock market is concerned, the average share price is an overall level reflecting the changes of various stock prices, which is usually expressed as an arithmetic average. By comparing the average stock prices in different periods, people can know the changes of various stock prices. Stock index is a relative index that reflects the changes of stock prices in different periods, that is, the percentage of the average stock price in the first period as the benchmark of the average stock price in another period. Through the stock index, people can know the percentage of stock price rising or falling relative to the base stock price during the calculation period. Because the stock index is a relative index, it can measure the change of stock price more accurately than the average stock price in a long period of time.
1. Calculation of average share price
The average stock price reflects the absolute level of listed stock prices at a certain moment, which can be divided into three categories: simple arithmetic stock price average, revised stock price average and weighted stock price average. People can see the changes and trends of stock prices by comparing the average stock prices at different times.
(1) simple arithmetic stock price average
Simple arithmetic stock price average is obtained by dividing the sum of daily closing prices of sample stocks by the number of samples, namely:
Simple arithmetic average stock price =(P 1+P2+P3+? +Pn)/n
Before 1928 10, the first average share price in the world-Dow Jones average share price was calculated by simple arithmetic average method.
Now suppose that four stocks, A, B, C and D, are sampled from a stock market, and the closing prices on a certain trading day are 10 yuan, 16 yuan, 24 yuan and 30 yuan, respectively, to calculate the average stock price of this market. Substituting the above figures into the formula, we get:
Average share price =(P 1+P2+P3+P4)/n
=( 10+ 16+24+30)/4
=20 (yuan)
Although the simple arithmetic of stock price average is simple, it has two shortcomings: First, the weight of various sample stocks is not considered, so it is impossible to distinguish the different effects of sample stocks with different importance on stock price average. Second, when the sample shares distribute bonus shares and increase capital in share split, the average share price will break and lose continuity, which makes it difficult to compare the time series before and after. For example, if the above-mentioned D shares are split into three shares with 1 share, the share price will inevitably be lowered from 30 yuan to 10 yuan. The average value at this time is (10+16+24+10)/4 =15. That is to say, due to the technical changes in the division of D shares, the average share price has dropped from 20 yuan to 15 yuan (this has not taken into account other factors that affect the stock price changes), which obviously does not meet the requirements of taking the average value as an indicator to reflect the stock price changes.
(2) The average number of shares after revision.
There are two revised average stock prices:
One is divisor correction method, also called track correction method. This is a method for calculating the average stock price created by Dow Jones in the United States at 1928. The core of this method is to find a constant divisor, so as to correct the changes of the average share price caused by stock split, capital increase, bonus and other factors, and maintain the continuity and comparability of the average share price. The specific method is to divide the new total share price by the old average share price to find a new divisor, and then divide the total share price in the calculation period by the new divisor to get the revised average share price. Namely:
New dividing line = changed new total share price/old average share price
Revised average share price = total share price in the reporting period/new divisor
In the above example, the divisor is 4, and the adjusted new divisor should be:
New divisor = (10+16+24+10)/20 = 3. If the new divisor is substituted into the following formula, then:
The average value of the revised stock price = (10+16+24+10)/3 = 20 (yuan) is the same as that calculated when it is not divided, and the stock price level will not change due to stock split.
The second is the stock price correction method. The stock price correction method is to restore the stock price after stock breakdown and other changes to the stock price before the change, so that the average stock price remains unchanged. The average value of 500 stock prices compiled by The New York Times, USA, is calculated by the stock price correction method.
(3) Weighted average share price
The weighted average stock price is the average stock price calculated by weighted average according to the relative importance of various sample stocks, and its weight (Q) can be the number of trading stocks, the total market value of stocks, the stock circulation, etc.
2. Calculation of stock index
Stock index is a relative index reflecting the changes of stock prices at different time points. Usually, the stock price in the reporting period is compared with the fixed base period price, and the ratio of the two is multiplied by the index value of the base period, which is the stock index in the reporting period. There are three methods to calculate stock index: one is relative method, the other is comprehensive method, and the third is weighting method.
(1) relative method
The relative method, also known as the average method, is to calculate the stock index of each sample first. Add up and get the arithmetic average of the total. Its calculation formula is:
Stock index = sum of n sample stock indexes /n
British economists use this method to calculate the common stock index.
(2) Comprehensive method
The comprehensive method is to add the base period and reporting period prices of sample stocks respectively, and then compare them to get the stock index. Namely:
Stock index = sum of stock prices in the reporting period/sum of stock prices in the base period.
Substitution number:
Stock price index = (8+12+18)/(5+8+10+15) = 52/38 =136.8.
That is, the share price in the reporting period rose by 36.8% compared with the base period.
Judging from the calculation of stock index by average method and comprehensive method, the factors such as the different circulation and trading volume of various sample stocks and the different influence on the stock price of the whole stock market are not taken into account, so the calculated index is not accurate enough. In order to accurately calculate the stock index, it is necessary to add weight, which can be either volume or circulation.
(3) Weighting method
The weighted stock index is weighted according to the relative importance of sample stocks in each period, and its weight can be the number of shares traded and the stock circulation. According to the time division, the weight can be the number of basic options or the number of reported options. The index weighted by the number of shares traded in the base period (or circulation disk) is called Rasbel index; An index weighted by the number of stocks traded (or circulated) during the reporting period is called the quotation index.
Rasbell index focuses on the number of shares traded in the base period (or circulation), while Paixu index focuses on the number of shares traded in the reporting period (or circulation). At present, most stock indexes in the world are Pais indexes.