Arithmetic Index

Dictionary Says

Definition of 'Arithmetic Index'

An index of securities that uses an arithmetic sum to determine changes in the index without taking the relative size of the securities into account. An arithmetic index of stocks does not incorporate weightings based on market capitalization, price, or any other metric, but merely calculates the raw changes in each component, then divides the sum by the number of index components.

Also known as an "unweighted index".

Investopedia Says

Investopedia explains 'Arithmetic Index'

Most stock indexes are market-cap weighted, which means that the largest companies will exert a larger influence on the index that the smallest. The Standard & Poor's 500 Index and the Nasdaq-100 are both market-cap weighted, while the Dow Jones Industrial Average (DJIA) is price-weighted. The Value Line index is calculated arithmetically, although few other major indexes fail to account for the size of their components in some way.


Related Definitions

  • Capitalization-Weighted Index

    A type of market index whose individual components are weighted according to their market capitalization, so that larger components carry a larger percentage weighting. The value of a ...
    Read More »
  • Market Capitalization

    The total dollar market value of all of a company's outstanding shares. Market capitalization is calculated by multiplying a company's shares outstanding by the current market price of ...
    Read More »
  • Standard & Poor's 500 Index - S&P 500

    An index of 500 stocks chosen for market size, liquidity and industry grouping, among other factors. The S&P 500 is designed to be a leading indicator of U.S. equities and is meant to ...
    Read More »
    • Arithmetic Mean

      A mathematical representation of the typical value of a series of numbers, computed as the sum of all the numbers in the series divided by the count of all numbers in the series. ...
      Read More »
    • Geometric Mean

      The average of a set of products, the calculation of which is commonly used to determine the performance results of an investment or portfolio. Technically defined as "the 'n'th root ...
      Read More »

Articles Of Interest

Partner Links