This chart breaksdown S&P 500 annual earnings per share growth into three components—margins, revenues, and buybacks. Coming out of the financial crisis, as well as the recession in the early 2000's, margins were the main driver of earnings growth, as revenues were lackluster and companies were not in a position to buy back shares. However, what we have observed is that over the course of a cycle, the contribution from both buybacks and revenue tends to increase. This makes sense as companies find themselves in better financial shape, and economic growth accelerates back to a more normal pace.