"The surprise outcome in Argentina’s primary vote roiled the nation’s financial markets, sending the S&P Merval Index plunging 48% in dollar terms.
That marked the second-biggest one-day rout on any of the 94 stock exchanges tracked by Bloomberg going back to 1950. Sri Lanka’s bourse tumbled more than 60% in June 1989 as the nation was engulfed in a civil war."
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