From 1927 to 2017, the U.S. stock market has delivered a hefty average return of about 11% per annum. The U.S. average stock market return is high in stark contrast to the average returns on bonds, currencies, mutual funds, exchange funds, warrants, and commodities such as gold, silver, oil, and wheat. 

Behavioral economists such as Nobel Laureate Richard Thaler have coined this macrofinancial anomaly *the equity premium puzzle*.

This equity premium puzzle suggests that the U.S. double-digit performance is too high to reasonably reflect the typical investor's relative risk aversion in light of low consumption growth.

While many scholars strive to resolve this equity premium puzzle with complex math models, some recent evidence suggests that the American stock market experience proves to be the exception that defies the rule of thumb.

In other words, the American stock market stands out of the international crowd in terms of long-term average aggregate performance.

Positive U.S. investor sentiment highlights the long-term outperformance of the U.S. stock market relative to many other asset classes.

U.S. stocks remain the primary investment vehicle for most global institutional investors and North American retail investors.

Information technology usage, diffusion, and proliferation have spurred the U.S. spectacular stock market vibrancy over the past few decades.