The Standard and Poors 500 index (SPX) closed today at 5,408, down 95 points or -1.7%. SPX opened the week at 5,624, closing down 3.8% for the week. Trading volume was above the 50-day moving average (dma) Tuesday and Friday but below average on Wednesday and Thursday.

VIX, the volatility index for the S&P 500 options, closed today at 22.4%, up 2.5 points. VIX opened Tuesday at 15.8% and spiked up over 20% and stayed in that neighborhood the balance of the week.

I track the Russell 2000 index with the IWM ETF, which closed today at 208, down four points or -1.9%. IWM was down almost five percent this week.

The NASDAQ Composite index closed today at 16,691, down 437 points or 
-2.6%. NASDAQ opened the week at 17,585, setting up a weekly loss of 5%. NASDAQ’s trading volume remained at or below the 50 dma all week.

I often make the mistake of looking for rational explanations for the market moves. When SPX dropped significantly earlier this week, the explanation by the talking heads was that the ADP private payrolls number at 99k was “below expectations”. Today’s explanation was that the jobs report at 142k jobs, up from last month’s 89k was “weak”. Last month was weak; this month was up.

Last week, I relayed the Stock Trader’s Almanac citation to you that September is historically the weakest month of the year for the stock market. Maybe I should have paid attention.

Today’s market decline seemed extreme to me. In particular, if one watched the SPX one minute chart today, it was uniformly down all day. That is unusual; normally, there is an ongoing tug of war with several ups and downs.

Based on my assumption of an extreme in trading today, I held several positions. We’ll see if that was a mistake.