National Association of Securities Dealers

, the parent organization of the


stock market, wants the

Securities and Exchange Commission

to delay the move to pricing stocks in decimals until next year.

The SEC currently plans to phase in

decimalization, replacing fractional stock prices, beginning July 3.

"In light of the explosion of transaction volume and quotations levels in both the equity and options markets, however, we believe the shift to begin trading in decimals this year would impose unacceptable risks," Frank Zarb, chairman and chief executive of the NASD, wrote to

Arthur Levitt

, chairman of the SEC, in a letter dated Monday and released late Tuesday afternoon.

He continued his appeal by saying: "Nasdaq has been growing faster than other markets, so it is logical that we are more sensitive to capacity issues. We will not put investors and the market at risk by forging ahead too soon."

According to the NASD, the capacity increase has been tremendous. Average share volume per day on the Nasdaq has more than doubled, from 791 million in 1998 to 1.7 billion from January to Feb. 18, 2000. Average daily quotation message traffic has more than tripled, from 1.025 billion to 3.870 billion in the same period.

"We have received the letter and don't have a response to it at this time," said Joanne Cronrath Bamberger, a spokeswoman for the SEC.

The request for a delay is supported by the

Securities Industry Association

"in order to ensure the integrity of the markets," the SIA said in a statement. The SIA represents more than 740 securities firms, including investment banks, broker-dealers and mutual fund companies.

As for the

New York Stock Exchange

, a spokesman said, "If Nasdaq is unable to switch to decimals in accordance with the SEC's timetable, we have a responsibility, even though the NYSE is ready for decimalization, to seek industry and government input as to what's best for investors."