Stocks haven’t done well in the month of September. The annual Stock Trader’s Almanac made it into a poem:
 
September is when leaves and stocks tend to fall
On Wall Street it s the worst month of all.
 
“For the blue chips it’s the worst month of all” was cited in 1990 and has been the less-frequently used second verse.
     
       
11 September 1990, Indiana (PA) Gazette, “Analysts say stock market to rebound,” pg. 8, col. 1:
“September is when leaves and stocks tend to fall//For the blue chips it’s the worst month of all,” is the way an “Almanac” verse puts it.
 
Chicago (IL) Tribune
Dreadful month ends at year’s lows
October 01, 2002|By Bill Barnhart.
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Cruder verse appears in the last two annual editions of the “Stock Trader’s Almanac”:
 
“September is when leaves and stocks tend to fall;
For blue chips it’s the worst month of all.”
 
Chronically Biased
September 13, 2004, 12:00 PM
Does The Month Of September Forecast Presidential Elections?
By Steettalk Advisors
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Ahh! The month of September, the end of summer and the start of the business year, the end to vacations and the beginning of the school year. Just as April showers bring May flowers – “September is when leaves and stocks tend to fall – and on Wall Street it’s the worst month of all.”
 
Google Books
Stock Trader’s Almanac 2005
By Jeffrey A. Hirsch, Yale Hirsch, Hirsch Organization
Hoboken, NJ: John Wiley & Sons
2005 (38th edition)
Pg. 82:
September is when leaves and stocks tend to fall
On Wall Street it s the worst month of all.
 
Safe Haven
September 12, 2006
Will September Rain on the Bulls Parade?
by Clif Droke
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That about puts it in perspective for the first half of September but what about the second half of the month? There’s an old Wall Street saying: “September is when leaves and stocks tend to fall, on Wall Street it’s the worst month of all.” This adage applies mainly to the second half of the month.
 
The Business Insider
Tomorrow Is SEPTEMBER
Vincent Fernando
Aug. 31, 2009, 3:59 PM
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“September is when leaves and stocks tend to fall. On Wall Street it’s the worst month of all.”