Index

Definition of 'Index'


A statistical measure of change in an economy or a securities market. In the case of financial markets, an index is an imaginary portfolio of securities representing a particular market or a portion of it. Each index has its own calculation methodology and is usually expressed in terms of a change from a base value. Thus, the percentage change is more important than the actual numeric value.

Stock and bond market indexes are used to construct index mutual funds and exchange-traded funds (ETFs) whose portfolios mirror the components of the index.

Investopedia explains 'Index'


The Standard & Poor's 500 is one of the world's best known indexes, and is the most commonly used benchmark for the stock market. Other prominent indexes include the DJ Wilshire 5000 (total stock market), the MSCI EAFE (foreign stocks in Europe, Australasia, Far East) and the Lehman Brothers Aggregate Bond Index (total bond market).

Because, technically, you can't actually invest in an index, index mutual funds and exchange-traded funds (based on indexes) allow investors to invest in securities representing broad market segments and/or the total market.



comments powered by Disqus
Hot Definitions
  1. 80-10-10 Mortgage

    A mortgage transaction in which a first and second mortgage are simultaneously originated. The first position lien has an 80% loan-to-value ratio, the second position lien has a 10% loan-to-value ratio and the borrower makes a 10% down payment. 80-10-10 mortgage transactions are piggy-back mortgage transactions, and are frequently used by borrowers to avoid paying private mortgage insurance.
  2. Passive ETF

    One of two types of exchange-traded funds (ETFs) available for investors. Passive ETFs are index funds that track a specific benchmark, such as a SPDR. Unlike actively managed ETFs, passive ETFs are not managed by a fund manager on a daily basis.
  3. Walras' Law

    An economics law that suggests that the existence of excess supply in one market must be matched by excess demand in another market so that it balances out. So when examining a specific market, if all other markets are in equilibrium, Walras' Law asserts that the examined market is also in equilibrium.
  4. Market Segmentation

    A marketing term referring to the aggregating of prospective buyers into groups (segments) that have common needs and will respond similarly to a marketing action. Market segmentation enables companies to target different categories of consumers who perceive the full value of certain products and services differently from one another.
  5. Effective Annual Interest Rate

    An investment's annual rate of interest when compounding occurs more often than once a year. Calculated as the following:
  6. Debit Spread

    Two options with different market prices that an investor trades on the same underlying security. The higher priced option is purchased and the lower premium option is sold - both at the same time. The higher the debit spread, the greater the initial cash outflow the investor will incur on the transaction.
Trading Center