Is It Too Late to Buy American Express Stock?

Shares of this high-flying payments leader have plenty of upside. Shares of American Express (AXP 0.28%) have skyrocketed to an all-time high with a 44% return this year, outperforming the 20% gain in the S&P 500 index. The financial services giant has benefited from resilient macroeconomic conditions, driving solid growth and stronger earnings. Shareholders have had plenty to cheer about lately. On the other hand, investors on the sidelines may wonder if it's too late to jump in and buy shares. Can the ral ...