
We all see the numbers at the end of the news before the weather, ‘the ASX was up 1.5% today whilst the Dow Jones was down 0.7%’ but what does it all mean. Stock market indices are a measurement of the value of a particular section in the stock market. The two most common methods to help determine the price of indices are by either the capitalisation-weighted (market-weighted) or price-weighted method. Capitalisation-weighted indices factor in the size of the company with the larger capitalised companies having more influence. Conversely a price-weighted index takes into account the market price of the share and places greater influence on individual share prices.
Some of the most common indices are:
ASX 200: is the index consisting of the capitalisation-weighted largest 200 companies listed on the Australian Stock Exchange. Some of the companies include the well known Big 4 banks, Woolworths, Telstra, Wesfarmers as well as mining companies Rio Tinto and BHP Billiton.
All Ordinaries: the oldest index in Australia, the All Ords consists of the largest 500 companies on the ASX using the capitalisation-weighted method. The index makes up 95% of the total value of all shares listed on the ASX.
S&P 500: the most well known index around the world, the Standard & Poors 500 is an index of the largest 500 companies by market capitalisation. The shares have to be listed on the NYSE or NASDAQ (two largest stock exchanges located in New York). The shares must also pass liquidity tests in order to qualify. It is often used as an indication of how the US economy is going.
Dow Jones: the Dow Jones Industrial Average is a price-weighted index containing 30 of the largest companies in the US. The index has kept its name for historical purposes but now consists of companies in various industries.
FTSE 100: the Financial Times Stock Exchange is an index of the largest 100 shares listed on the London Stock Exchange weighted by capitalisation. Companies included within the index include BP, HSBC, Shell and Vodafone.
Image: http://www.istockphoto.com/au/photos/stock-market

