Sell in May and Go Away

The expression "sell in May and go away" refers to the notion that the stock market tends to underperform in the late spring and summer months.

The idea is that you sell all of your stock holdings (or, at least, trim down your holdings) and rebuy them in the fall (typically November).

By doing this, it is thought, you will be avoiding the "weak" months of June, July, August, September and October.

Does this saying hold true? Well, let's look at the historical performance of the DJIA, NASDAQ and S&P 500 during the months listed above:

DJIA

Return in June has been 0.51%
Return in July has been 1.5%
Return in August has been 0.75%
Return in September has been -1.3%
Return in October has been 0.01%

NASDAQ

Return in June has been 0.77%
Return in July has been 0.03%
Return in August has been 0.24%
Return in September has been -0.53%
Return in October has been 0.34%

S&P 500

Return in June has been -0.06%
Return in July has been 1%
Return in August has been 0.05%
Return in September has been -0.46%
Return in October has been 0.62%

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Compared to Nov-May, the three indexes above have clearly underperformed between June-October, which seems to prove the "sell in May and go away" theory.