Market's Seasonality May Be Especially Important This Year

It’s that time of year again when I always remind you of the market’s seasonality, its proven tendency to make most of its gains between November and May, and experience most of its losses in the opposite period.

I get a kick out of people who dismiss it as an interesting theory that doesn’t always work. It’s not theory. It’s proven fact. In spite of the few years when it has not worked, investing over the long-term based on the market’s seasonality significantly outperforms the market, and with much less risk.

Don’t take my word for it. Academic studies provide clear evidence.

For instance, a 27-page study published in the prestigious American Economic Review in 2002 concludes, “We found that this inherited wisdom of Sell in May to be true in 36 of 37 developed and emerging markets”

It went on to say that, “A trading strategy based on this anomaly would be highly profitable in many countries. The annual risk-adjusted outperformance ranges between 1.5% and 8.9% annually depending on the country being considered. The effect is robust over time, economically significant, unlikely to be caused by data-mining, and not related to taking excess risk.”

Another study in 2008 at the New Zealand Institute of Advanced Study, which focused solely on the U.S. stock market, concluded that “All U.S. stock market sectors, and 48 out of 49 U.S. industry sectors performed better during the winter months than summer months in our sampling from 1926-2006.”

Let’s put the fact that it doesn’t work every year in context.

To begin with, no strategy, particularly buy and hold, works every year. And that is also true of seasonality.

For instance, it underperformed in 2003 and 2009. In those years the market made gains in the winter months, and then, fuelled by massive government stimulus programs, continued still higher during the summer months when a seasonal investor would have been invested in something other than stocks.

But the seasonal investor did not lose money by being out of the market in the unfavorable season in those years. He or she merely missed further gains. 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. Those losses can be substantial, with investors giving back much, if not all of the gains made in the previous favourable season. For instance, from May 1st to its low during the summer months, the S&P 500 lost 22% of its value in 2001, 24% in 2002, 38% in 2008, and even 16% in the early summer correction in the positive year last year. Those are the experiences that created the ‘lost decade’ that buy and hold investors experienced but which seasonal investors avoided.

Why might seasonality be even more important this year than in other years?

Negatives are piled up against the economy and market to a degree not seen in a number of years. They include rising inflation; global central banks raising interest rates to ward off inflation, which is also likely to slow their economic growth; signs of the U.S. economy slowing again (sharp declines in home sales, durable goods orders, and consumer confidence); the coming end of the Federal Reserve’s QE2 stimulus efforts in June; and the austerity measures Congress will be forcing on the country in efforts to bring the record budget deficit under control.

Then there is the high level of investor bullishness usually seen near market tops. For instance, the Investors Intelligence Sentiment survey shows bullishness has jumped up to 57%, while bearishness has fallen to just 15.7%. That spread of 41.6% is considered to be in a danger zone. The last time it reached 40% was in October, 2007, as the market topped out into the 2007-2009 bear market.

So, fair warning. Seasonality is liable to be even more important this year than in most years.

The traditional seasonality maxim, ‘Sell in May and Go Away’, calls for buying November 1 and selling on May 1 of the following year. Those dates were the basis for the academic studies mentioned earlier.
But obviously a positive market move does not begin and end on the same day each year. So in my 1999 book Riding the Bear – How to Prosper in the Coming Bear Market, I introduced my Seasonal Timing Strategy. It uses a technical indicator that tracks market momentum reversals to better identify the entries and exits. Over the last 40 years, its exit signals have been as early as April 20, and as late as June 20.

The modification significantly improved the already impressive performance of the basic ‘Sell in May and Go Away’ seasonal strategy. In a recent article on MarketWatch, Mark Hulbert wrote that the Hulbert Financial Digest has only been tracking the performance since mid-2002, and since then “Harding’s modification of the Sell In May and Go Away indicator produced an 8.2% annualized return . . . with 37% less risk.” That significantly beat the performance of the S&P 500.

 In the interest of full disclosure, I and my subscribers have the portion of assets following our seasonal strategy 100% invested in the 30-stock Dow until the next exit signal is generated.

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