1985: April Fool! Coca-Cola marketing whizzes Sergio Zyman and Brian Dyson make their final presentation of the business plan that convinces Coke's top two executives, Roberto Goizueta and Donald Keough, to replace Coke's original formula with the sweeter, Pepsi-like New Coke. It will go down as one of the worst marketing fiascos in history.

Frederick Allen, Secret Formula: How Brilliant Marketing and Relentless Salesmanship Made Coca-Cola the Best-Known Product in the World (HarperBusiness, New York, 1994), p. 409.

1971: April Fool! Here's a dopey-sounding idea for a new business: The former manager of a market-timing mutual fund with one of the worst records in the country (the Investment/Indicators Fund, which had lost 20.7% in 1969) founds a brokerage firm to undercut Wall Street's trading commissions. He calls his fledgling company First Commander. Only later does he rename it after himself: the Charles Schwab Corp.

Corporate communications dept., The Charles Schwab Corp.

1968: Today's trading volume, 17.73 million shares, finally surpasses the record daily volume set almost 39 years earlier on October 29, 1929.

"Today in NYSE History," at www.nyse.com/about/TodayInNYSE.html

1930: April Fool! In one of the biggest "suckers' rallies" of all time, the total market value of New York Stock Exchange-listed companies hits $67.5 billion, up roughly 40% from its trough in the Great Crash of 1929. As the New York Fed cuts interest rates yet again to just 3.5% (down from 6% in 1929), investors turn bullish, and many leading stocks, like RCA and Columbia Graphophone, roughly double from their 1929 lows. By year-end, however, stocks are down more than 40% from here.

Barrie A. Wigmore, The Crash and Its Aftermath: A History of Securities Markets in the United States, 1929-1933 (Greenwood Press, Westport, CT, and London, 1985), pp. 129, 137-140.

1913: April Fool! The stock market surges by 2.7%, as the Dow Jones Industrial Average jumps 2.15 points to close at 82.30. The day before, J.P. Morgan, whose protracted illness had glowered over the market like a storm cloud, finally died of a stroke brought on by "nervous prostration." The market responds with a quick "relief rally," but the Dow ends up closing out the year at 58.75, a 28.6% decline from today's close.

Jean Strouse, Morgan: American Financier (Random House, New York, 1999), pp. 680-681

1901: April Fool! Northern Pacific railway stock hits $96 a share as E.H. Harriman and J.P. Morgan fight for control of the railroad. By May 9, the stock will peak at an astonishing $1,000 per share — a 942% return in five weeks. Then it collapses.

Jean Strouse, Morgan: American Financier (Random House, New York, 1999), pp. 421, 424.