The S&P/TSX Composite Index is the leading index for the Canadian stock market, according to S&P Dow Jones Indices. S&P Dow Jones Indices, which oversees U.S. indices such as the S&P 500, manages and calculates the S&P/TSX Composite using real-time and historical data provided by the Toronto Stock Exchange.
The index launched as the TSE 300 Composite Index in 1977 with 300 companies included in its calculations, explains RateSupermarket.ca. In 2002, Standard & Poors acquired the index and amended its rules. S&P reduced the number of industry sectors covered by the index from 14 to 10 and adjusted the composition of the index from a fixed set of 300 companies to a variable number. In fact, the number of companies in the index often fluctuates. For example, it covered 204 companies in 2009 and 256 companies in 2011.
As of 2015, the S&P/TSX Composite Index covers 242 large Canadian companies that have market capitalizations ranging from 284 million Canadian dollars ($209 million) to over CA$113 billion ($83 billion), notes S&P Dow Jones Indices. The index's largest industries are financials, energy, materials, industrials and consumer discretionary. The three largest companies in the index are each financial institutions: Royal Bank of Canada, Toronto-Dominion Bank and Bank of Nova Scotia Halifax.