An Index is a set of prices that are published for a commodity or product, usually derived from trading data, using an open and independent method

Detail

An index consists of a set of time periods, with an associated price (or set of prices) for a particular commodity or product for each of the time periods:

The time periods are sometimes called grid points (or gridpoints)

A typical index has daily granularity forward from the date it is published for a number of days, then monthly for some months, then quarterly, seasonal and annual

For each time period there may be a bid price, an offer price, and an average (mean) price

Indexes are usually published at the end of each trading day, and represent some sort of average of the prices that Forward and Futures contracts actually traded at on that day (or for a pre-defined period of the day)

Various organizations publish indexes for different commodities and products:

Exchanges publish indexes for the various products they offer

Independent analysts publish indexes for commodities in markets they specialize

Trading organizations use indexes to:

Derive forward (valuation) curves

Fix in floating prices of floating price trades

Agree forward valuation of trade portfolios with counterparties for netting agreements

There is some similarity between indexes and curves since they are both sets of time-series data. The main differences are:

Indexes are published by independent organizations, and are available to any organization that wishes to subscribe to them

Indexes only relate to prices of commodities and products

Curves are usually created by, and proprietary to, the trading organizations that create them

Curves consist of any time-series data, including valuation, volatility, interest rates etc.