The American Express Company (NYSE: AXP) reported its third-quarter earnings earlier this month, and shares reacted positively to the news. The credit card company's adjusted revenue grew to $10.1 billion, a 10% increase year over year, marking the sixth consecutive quarter of at least 8% growth. The company's diluted earnings per share (EPS) rose to $1.88, a 25% increase over last year's third quarter.The strong top- and bottom-line growth was driven by a number of wide-ranging factors.