The Five Best Months in S&P 500 History

Not long ago, we mined our S&P 500 data to find the five worst month-long periods ever for investors in the stock market. And now, for the sake of balance, we're extracting the five best month-long periods ever for the S&P 500.

As we noted previously, we can't precisely answer which calendar month since January 1871 was the worst given our S&P 500 data, since the value we have for each month is the average of the closing value of the S&P 500 index on every trading day during the course of that month. Consequently, our data doesn't include what value it started out at in the beginning of the month of interest, what highs or lows it may have hit during the course of that month, how long it was at any given level, or where it ended up on the last trading day of the month.

But, what we do have in the average value of the S&P 500 index for each month over its entire history since 1871 allows us to measure its general performance between any two months, even if just one month apart.

So, we scanned our average monthly data to find the five best average month-long investing periods captured by our data, which we've summarized in the table below. As before, we're looking purely at the value of the index itself, without considering factors that would influence an investor's actual returns, such as inflation, reinvestment of dividends, taxes, commissions or other transaction fees:

The Five Best Months for the S&P 500 Index Value
Starting Month	Ending Month	Starting Index Value	Ending Index Value	Percentage Gain
July 1932	August 1932	5.01	7.53	+50.3%
April 1933	May 1933	6.23	6.89	+28.7%
June 1938	July 1938	10.21	12.24	+19.9%
May 1933	June 1933	8.87	10.39	+17.1%
August 1982	September 1982	109.70	122.40	+11.6%

As we've noted elsewhere in looking at the best and worst case returns on investments in the S&P 500 for periods of time ranging from 1 through 50 years long, the only consistent factor that shared by the best returns in the stock market index is that these periods tend to coincide with the end of the worst periods of time for investing in the stock market!

Previously on Political Calculations

• The Worst Returns of the S&P 500 vs The Safest Investments on Earth
  
• The S&P 500's Golden Years - Did you ever wonder what the best bull years the stock market ever had? We find the best 1 through 50 year periods ever!
  
• The Worst Returns Ever for the S&P 500 - We identify the dates that go along with the worst returns ever (after inflation) for the S&P 500!
  
• The S&P 500 at Your Fingertips - Our signature tool provides historical market data for the S&P 500 going all the way back to January 1871, and finds the rates of return between any two months both before and after inflation and with or without dividend reinvestment!
  
• Lemony Snicket and the S&P 500 - Our tool that takes the best, worst and most average investment returns ever from the S&P 500, and asks what if your investments had these returns?
  
• Mapping S&P 500 Performance, Since 1871 - our analysis that led to our model of the best and worst case performance ever for the S&P 500.
  
• S&P 500: Best, Average and Worst Returns - our tool approximates the best, worst and average returns for investments of any length in the S&P 500 stock market index.