The consumer-price index leaped 0.5% in January to mark the biggest increase in five months. Inflation has re-emerged after a long period of dormancy; giving investors’ the jitters. Wall Street is worried rising prices will force the Federal Reserve to raise U.S. interest rates more aggressively and potentially choking off an economic expansion that’s almost nine years old. Stock markets started to tank in early February after the biggest yearly increase in hourly pay since 2009.