Even the very rich should invest in broad-market index funds — here’s why
1. Wealth of the richest Americans rose 22% in 12 months. 2. Their performance lags the S&P 500 by 1.5% annually over nine years. 3. Investing in the stock market isn't the primary source of their wealth. 4. Survivorship bias affects reported returns of the Forbes 400. 5. Most billionaires aren't heirs, but self-made entrepreneurs.