What Is a Price-Weighted Index?
A price-weighted index is a 澳洲幸运5官方开奖结果体彩网:stock index in which each company included in the index makes up a fraction of the total index proportional to that company's share stock price per share. In its simplest form, adding the price of each stock in the index and dividing by the total number of companies determines the index's value.
A stock with a higher price will be given more weight than a stock with a lower price and will thus have a greater influence on the index's performance.
Key Takeaways
- In a price-weighted stock index, each company's stock is weighted by its price per share, and the index is an average of the share prices of all the companies.
- Price-weighted indexes give greater weight to stocks with higher prices in terms of their contribution to the index value and changes in the index.
- A price-weighted index can be used to track the average stock price of a given market or industry.
Understanding a Price-Weighted Index
In a price-weighted index, a stock that increases from $110 to $120 will have the same effect on the index as a stock that increases from $10 to $20, even though the percentage move for the latter is far greater than that of the higher-priced stock. Higher-priced stocks exert a greater influence on the index's, or the basket's, overall direction.
To calculate the value of a simple price-weighted index, find the sum of the share prices of the individual companies, and divide by the number of companies. In some averages, this divisor is adjusted in order to maintain continuity in the event of stock splits or changes to the list of companies included in th꧂e index.
Price-weighted indexes are useful because the index value wil𒅌l be equal to (or at least 🐼proportionate to) the average stock price for the companies included in the index. This allows the construction of indexes that will track the average stock price performance of a specific sector or market.
One of the most popular price-weighted stocks is the 澳洲幸运5官方开奖结果体彩网:Dow Jones Industrial A💫verage (DJIA), which consists of 30 different stocks, or components. In this index, the higher-price stocks move the index more than those with lower prices, thus the price-weighted designation. The Nikkei 225 is another exam𝕴ple of a price-weighted index.
Other Weighted Indexes
In addition to price-weighted indexes, other basic types of weighted indexes include 澳洲幸运5官方开奖结果体彩网:value-weighted indexes and 澳洲幸运5官方开奖结果体彩网:unweighted indexes. For a value-weighted index, like those in the MSCI family of strategy indexes, the number of outstanding shares is a factor. To dete🔥rmine the weight of each stock in a value-weighted index, the price of the stock is multiplied by the number of shares outstanding.
For example, if Stock A has five million outstanding shares and is trading at $15, then its weight in the index is $75 million. If Stock B is trading at $30, but only has one million outstanding shares, its weight is $30 million. So, in a value-weighted index, Stock A would have more say in how🥂 the index moves than Stock B.
In an unweighted index, all stocks have the same impact on the index, no matter their share volume or price. Any price change in the index is based on the return percentage of each component. For example, if Stock A is up 30%, Stock B is up 20%, and Stock C is up 10%, the ind𒐪ex is up 20%, or (30 + 20 + 10)/3 (i.e., the number of stocks in the index).
Other types of weighted indexes include revenue-weighted, 澳洲幸运5官方开奖结果体彩网:fundamentally weighted, 🐭and float-adjusted. All have their posiꦬtives and negatives, depending on the investor's goals and market knowledge.