Historical Data

Historical data is information about a company's past, such as its revenues, earnings, and stock price action. In a sense, all data is historical data, since only what has occurred can be recorded. Therein lies the problem of historical data and stock prices, which are determined by expectations of a company's future cash flows, not those already reported. Nevertheless, historical data is essential for stock analysts, who crunch a company's historical data to predict its future course. Historical data is also key for technical analysts, who predict a company's stock price by focusing on its movement in the past. Historical data is probably least useful to mutual fund buyers: Because mutual fund performance is significantly determined by the prevailing market environment, historical data that shows which funds performed best in the last market cycle is unlikely to predict which will do well in the current one. Finally, language mavens will insist that only a tiny fraction of historical data is "historic data," which is confined to epoch-changing items like July 4, 1776, and the Stock Market Crash of 1929.