Contributing to the drop was a five-minute selling wave ending 15 minutes before the closing bell.

"The selling wave struck both markets at the same time."

In foreign stock markets, two forces explained the size of the selling wave.

In a steep one-hour selling wave, the Dow plunged nearly 60 points from its high for the day.

Later in the day, the selling wave moved eastward.

Markets A late selling wave wiped out a stock-market rally.

An earnings warning from Motorola started a selling wave that not even more mergers in financial services could overcome.

A 15-minute selling wave near the close accounted for 11 points.

The selling wave forced each of the 18 monthly gas futures contracts lower, with the January 1994 contract falling 7 cents, to $2.23.

A 12-minute selling wave by program traders starting at 3:38 pushed the market down sharply.