The NZX 50 Index (NZ50) is the main stock market index in New Zealand. It comprises the 50 biggest stocks by free-float market capitalisation trading on the New Zealand Stock Market (NZSX). The calculation of the free-float capitalisation excludes blocks of shares greater than 20% and blocks between 5% and 20% that are considered strategic.
The index was introduced as the NZSX 50 Index in March 2003 and replaced the NZSE 40 Index as the headline index. It was renamed the NZX 50 Index in late 2005. The NZSE 40 Capital Index replaced the Barclays index in 1992, although the Barclays index is still compiled by the NZX but not made widely available.
At December 11, 2015, the constituent companies of the NZX 50 were:
Coordinates: 41°17′23″S 174°46′46″E / 41.289709°S 174.779493°E
NZX Limited builds and operates capital, risk and commodity markets and the infrastructure required to support them. It also provides information, data and tools to support business decision making. NZX is the only registered securities exchange in New Zealand, and is also an authorised futures exchange. Its wholly owned subsidiary, New Zealand Clearing and Depository Corporation, is the operator of a designated settlement system under Part 5 of the Reserve Bank of New Zealand Act 1989.
NZX has offices across New Zealand and Australia. Its newest office is in Auckland, adjacent to the Britomart precinct. NZX’s Agri HQ is in Feilding and its Australian operation is based in Melbourne.
As of November 2014, NZX had a total of 258 listed securities with a combined market capitalisation of $94.1 billion.
NZX began life as a number of regional stock exchanges during the gold rush of the 1870s. In 1974 these regional exchanges were amalgamated to form one national stock exchange, the New Zealand Stock Exchange (NZSE).