Rate of return

Why Does the Stock Market Keep Going Up?

Many people were taken by surprise when the stock market reached new highs after the 2016 election, with the Dow Jones industrial average (DJIA) breaking 20,000. But the recent record highs are only the latest in a long trend of stock market growth extending back well over 100 years.

The average rate of return for the DJIA since 1896 is about 7 percent when adjusted for inflation. Looking at a broader representation of the overall stock market, the average rate of return for the Standard & Poor’s (S&P) 500 index since it’s inception in 1928 is about 10 percent per year.

Of course, if you pay attention to the stock market, you know that stocks do not move steadily up all the time. Sometimes there are sudden market declines, such as the crash of 1929 that led to the Great Depression, or the 2008 collapse that led to the Great Recession. Sometimes there are long periods of market stagnation when stock prices do not go up much at all, such as during the 1970s. But over time, the long-term trend has been that stock values keep on pushing up, even after setbacks, and routinely go on to break record highs.

What makes stock values keep going higher and higher?

Investors think stocks will go up

Investors who decide to put money into the stock market select individual stocks and stock funds based on the financial performance of the businesses in the portfolio. Ultimately, investors weigh the potential for a stock to go up versus the risk that it will go down during their investment window.

Sometimes “irrational exuberance” seems to play a big role in driving stock prices. In a hot housing market, investors will pay essentially any price to buy a property if they are confident the price will go up, even if the price is not rational. Investors sometimes buy stock for the same reason — simply because they think someone else will pay more for it when they want to sell and they don’t want to miss an opportunity to make a big gain. In some extreme…