May officially marks the beginning of the “Worst Six Months” for the DJIA and S&P. To wit: “Sell in May and go away.” Our “Best Six Months Switching Strategy,” created in 1986, proves that there is merit to this old trader’s tale. A hypothetical $10,000 investment in the DJIA compounded to a gain of $1,180,836 for November-April in 73 years compared to just $3,323 for May-October (STA 2024, page 54). The same hypothetical $10,000 investment in the S&P 500 compounded to $977,443 for November-April in 73 years compared to a gain of just $13,335 for May-October.
May has been a tricky month over the years, a well-deserved reputation following the May 6, 2010 “flash crash”. It used to be part of what we once called the “May/June disaster area.” From 1965 to 1984 the S&P 500 was down during May fifteen out of twenty times. Then from 1985 through 1997 May was the best month, gaining ground every single year (13 straight gains) on the S&P, up 3.3% on average with the DJIA falling once and NASDAQ suffering two losses.
In the years since 1997, May’s performance has been erratic; DJIA up fourteen times in the past twenty-six years (four of the years had gains exceeding 4%). NASDAQ suffered five May losses in a row from 1998-2001, down –11.9% in 2000, followed by fourteen sizable gains of 2.5% or better and seven losses, the worst of which was 8.3% in 2010 followed by another substantial loss of 7.9% in 2019.
Since 1950, election-year Mays rank rather poorly, #9 DJIA and S&P 500, #8 NASDAQ and Russell 2000 and #7 Russell 1000. Average performance in election years has also been weak ranging from a 0.4% DJIA loss to a 0.6% gain by Russell 2000. Aside from DJIA, the frequency of gains in election year Mays is bullish, but down Mays have tended to be big losers. In 2012, DJIA, S&P 500, NASDAQ, Russell 1000 and 2000 all declined more than 6%.
Over the last 21 years, the first three days of May have historically traded higher, and the S&P 500 has been up 18 of the last 26 first trading days of May. Bouts of weakness often appear around or on the fourth, sixth/seventh, and twelfth trading days of the month while the last four or five trading days have generally enjoyed respectable gains on average, but the last day of May has weakened noticeably with only NASDAQ gaining ground.
Monday before May monthly option expiration is much stronger than monthly expiration day itself albeit weaker for small caps. S&P 500 has registered only ten losses in the last thirty-four years on Monday. Monthly expiration day is a loser nearly across the board except for Russell 2000 with a slight average gain (+0.01%). The full week had a bullish bias that is fading in recent years with DJIA down seven of the last eight and S&P 500 down six of the last seven. The week after options expiration week now tends to favor tech and small caps. NASDAQ has advanced in 24 of the last 34 weeks while Russell 2000 has risen in 26 of the last 34 with an average weekly gain of 0.88%.