Stock market volatility is back! by Scott DeCarlo @FortuneMagazine 7:44 AM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons The S&P 500 just posted its first four-week loss since August 2011, and with it came some dizzying ups and downs. Shares of Fortune 500 companies, indeed, were even wilder. What happened? There was tumult everywhere, as stocks of various energy, mining, and retail companies registered fleeting double-digit percentage swings. Click graphic to enlarge This story appears in the November 17, 2014 issue of Fortune.