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Greatest trading volume in the first hour

Greatest trading volume in the first hour
Who
NYSE
Where
United States (New York City,)
When
17 June 2005
The New York Stock Exchange saw the heaviest ever first hour of trading on 17 June 2005. Due to a quirk in the options and futures markets, 704 million shares were traded between 9.30am and 10.30am, rising to 1.92 billion shares in the course of the day.