Small caps are having a good year — but here’s why the S&P 500 will win in the end

America’s smallest public companies have been thriving this year in an economy that finally seems to reward them — lower interest rates, steady economic growth and a financial market once again hungry for risk. But beneath the surface, the fundamentals tell a different story — a reminder that the small-cap rally is being fueled more by optimism than earnings, and that these stocks may never run with the big dogs of the S&P 500.Large-cap outperformance has become particularly acute since the start of the cur ...