Gold prices are plunging as investors grow more confident about the global economy, according to AP. Gold fell $104, or 5.6 percent, to settle at $1,757 an ounce Wednesday. It's the steepest percentage drop since March 2008. Gold is still is up 24 percent for the year. Investors have been buying gold because of concerns about economic weakness in the United States and Europe as well as a stretch of severe volatility in financial markets that began in early August. Recent economic news has been more encouraging. Orders for long-lasting manufactured goods shot up 4 percent in the U.S. last month. That prompted investors to sell gold after it's big run-up. In other commodities trading, oil, other metals and agricultural products were mixed.