Many investors use closing prices reported in the newspapers to monitor their holdings.
But not all closing prices are the same, and the differences may be important to you. But a number of market centers now offer after-hours trading . Some financial publications and market data vendors use the last trade in these after-hours markets as the closing price for the day. For example, an investor might read on a company's website that its stock closed at one price but then see a much different price on the consolidated tape flashing across the bottom of her or his television screen. The Nasdaq Stock Market, which operates a similar system for trades in its securities, uses similar conventions.