TRUCKEE, Calif. — Investors hear many old clichs regarding the stock market. One saying that you may hear this time of year is to, “sell in May and go away.”Actually the original phrase was, “sell in May and go away, do not return until St. Leger’s Day.” The saying goes back to old England and referred to the fact that many investors and brokers in those days took most of the summer off and did not get back to work until the middle of September after the final horse race of the season on St. Leger’s Day, and there was very little movement in the stock market over the summer months.There has been a substantial amount of research done on the “sell in May and go away” theory. It’s also known as the “best six months strategy” and the research has produced some interesting results.Stock Trader’s Almanac did a study that ran from 1950 to 2009 on the Dow Jones Industrial Average. If you had invested $10,000 in the Dow on November 1st, 1950, sold your investment on May 1st, 1951, then repeated that process until 2009, your initial $10,000 investment would have grown to $527,388.Had you done the exact opposite and bought on May 1st then sold on November 1st you would have lost $474 over the 60-year period.A study by Securities Research Company on the Sandamp;P 500 from 1945 to the present showed that the price return on the Sandamp;P 500 yielded an average annual return of 4.1 percent. If had you sold in May each year and bought back in November your annualized return would have been 6.8 percent.They also ran a study over the 10 years that ran from 2001-2010 and found that the price return on a buy and hold strategy on the Sandamp;P 500 would have averaged 12.7 percent over those 10 years, and the switching strategy would have averaged 23.6 percent per year.Does this mean that everyone should sell out their portfolio and wait until November to get back into the market? No, there are a lot of other factors to consider, like the effect of dividends, tax consequences, trading costs and you own individual situation.There have also been years that were exceptions like 1995 when the Dow was up 10 percent over the summer season and 2009 when it went up 18.9 percent. Long term stock investors should always be prepared for some market volatility over the summer months.Kenneth Roberts is a Truckee based Registered Investment Advisor. Information on his money management service can be found at www.fusiontargetretirement.com or by calling 775-657-8065. Past performance does not guarantee future results. Consult your financial adviser before purchasing any security.