The writer is professor of finance at the WP Carey School of Business of Arizona State University
In 2017, I disseminated a research report assessing whether stocks outperform Treasury bills. It seems the report presented something of a Rorschach test, as observers drew starkly diverging interpretations from the same empirical facts.
The paper described long-term investment outcomes to stocks listed on the major US markets. It showed that the majority of individual stocks generate losses in the long run, and that, while the overall stock market increased investors’ wealth by many trillions of dollars, the net gain was concentrated in relatively few high-performing stocks.