The average return on FTSE 100 depends on the time period you look at and the method of calculation. Generally speaking, investing in the stock market involves risk and volatility, as the prices of shares can go up or down rapidly. Past performance is not a guarantee of future results. Some investors use FTSE 100 as a benchmark to compare their portfolio's performance against, but it's not the only or the best measure of success. As per the image, we can understand that Footsie has already given more than 6 times the return to the investors.