Fasten Your Seatbelts - Here Comes September!

Always remember, sell in September? Will the summer rally persist? Historically, September ranks as the worst month on average for all three major US indexes.

  • Avg down days for the Dow and S&P outnumber avg up days nearly 3 to 1
  • Numbers get worse following up Augusts

September - Market Stats: (US Indexes)
Dow: (Since 1896)

  • On average the Dow has declined -1.2% in September
    • Worst month on average overall
    • On a day-by-day basis, the Dow has been down 22 days out of the 30 days in September
    • On average, the Dow has dropped -2.13% in September, when following an up August
    • Up 41.1% of the time in September, average gains of 3.8% when up
    • Down 58.9% of the time in September, average loss of -4.7%, when down
  • The biggest September gain was in 1896, when the Dow finished up 12.8%
  • The biggest September loss was in 1931, when the Dow finished down -30.7%

S&P: (Since 1928)

  • On average the S&P has declined -1.3% in September
    • Worst month on average overall
    • On a day-by-day basis, the S&P has been down 22 days out of the 30 days in September
    • On average, the S&P has dropped -1.8% in September, when following an up August
    • Up 43.2% of the time in September, average gains of 3.2% when up
    • Down 55.6% of the time in September, average loss of -4.8% when down
    • Flat in September 1979
  • The biggest September gain was in 1939, when the S&P finished up 14.4%
  • The biggest September loss was in 1931, when the S&P finished down -30.5%

Nasdaq Composite: (Since 1971)

  • On average the Nasdaq has declined -1.0% in September
    • Worst month on average overall
    • On a day-by-day basis, the Nasdaq has been down 17 days out of the 30 days in September
    • On average, the Nasdaq has dropped -1.5% in September, when following an up August
    • Up 52.6% of the time, average gains of 3.5% when up in September
    • Down 47.4% of the time, average loss of -6.05% when down in September
  • The biggest September gain was in 1998, when the Nasdaq finished up 13%
  • The biggest September loss was in 2001, when the Nasdaq finished down -17%

CBOE Volatility Index VIX - September stats: (Since 1986)

  • On average the VIX has increased 8.2% in September, ranking as the #2 most volatile month. October ranks #1 with avg. gains of 13.7%
  • Up 56.5% of the time in September, average gains of 21.3% when up
  • Down 43.5% of the time in September, average loss of -8.7% when down
  • The most volatile September was in 2008 when the VIX rose 90.8% for the month
  • The least volatile September was in 2007 when the VIX fell -23.01% for the month
  • The VIX has closed above 30 in September 70 times

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