The Web site for the NYSE--which provides stock quotes, research and regulatory information--was inaccessible for about two hours near the end of the day after the markets closed.
"The site is experiencing connectivity problems, and it's being worked on now," NYSE spokesman Ray Pellecchia said this afternoon, adding that the company is working with IBM, its "Web site provider," to trace the problem. IBM could not be reached for confirmation.
The outage coincided with the NYSE's conversion to listing quotes for some stocks in decimals rather than in fractions, a change that is in response to the Securities and Exchange Commission's efforts to bring U.S. markets in line with the world. Many international exchanges already list prices in decimals.
Pellecchia said the site outage was not related to the move to decimal pricing.
Proponents of decimal pricing say that the system helps investors find better prices than the more limited system that is based on fractions such as 1/8 or 1/16.
Decimal pricing limits the price between buy and sell offers commonly known as the "spread." For example, a buyer could put in an order to buy shares at $20.09. Under fractional pricing, that same buyer might have to place an order at $20.125.
The following stocks traded in decimals today: Anadarko Petroleum, Forest City Enterprises, Federal Express, Gateway, Hughes Supply and MSC Software.