Mean expected rate of return

Calculating expected return is not limited to calculations for a single investment. It can also be calculated for a portfolio. The expected return for an investment portfolio is the weighted average of the expected return of each of its components. Components are weighted by the percentage of the portfolio’s total value that each accounts for. The average stock market return over the long term is about 10% annually. That's what buy-and-hold investors have historically earned before inflation. Every percentage increase in profit each year could mean huge increases in your ultimate wealth over time. To provide a stark illustration, $10,000 invested at 10% for 100 years turns into $137.8 million. The same $10,000 invested at twice the rate of return, 20%, does not merely double the outcome; it turns it into $828.2 billion.