But when an investor is in the market in unfavorable seasons in which the market experiences the serious declines that most often take place in unfavorable seasons, that investor actually loses money.

FORBES: Selling In May Is Very Good Advice This Year

But it works out so consistently that over the long-term it outperforms the market to a significant degree, while also avoiding large losses (since they most often occur in the unfavorable seasons), and while taking only 50% of market risk (since one is in the market roughly only six months out of every twelve).

FORBES: Even If You Sold In May, Should You Buy Back In Now?

In the other direction, by the time the exit date approaches in the spring there has usually been an impressive favorable season rally that has reversed sentiment, convincing many that this time is different, that seasonality will not be a factor, that the market will most likely continue to climb through its unfavorable season.

FORBES: Sell In May Could Still Come Into Play But Don't Bail Now

It says sell everything on May 1, and stay away until November 1, standing aside for the entire unfavorable period when history shows the market experiences most of its serious corrections, and only rarely experiences meaningful rallies.

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