But there is an important nature of volume that I don’t think he took into consideration. Everything else being equal, volume tends to be cyclical and follow a pattern. For example, it tapers off during holidays like Christmas and New Years (yellow squares on the chart). Volume is light from June to August - what is referred to usually as the summer doldrums. And it spikes for panic lows (you can see a few examples above).
But is there anything we can look to from recent low volume?
I started from using June 8th 2009 as a base; on Monday the amount of volume traded was 32% below a 60-day moving average of volume. In the prior week volume traded between 6 and 21% below the 60-day moving average of volume. So looking back to 1950 how many days in June did volume trade below the 60-day MA of volume by 30% or more?
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The majority of these cases occurred in the late 50s and early 60s with large number of light volume days populating June. But there was a dramatic shift from 1979 to 2009 with only the odd day here and there and no light June trading day in the nineties.
How did the S&P perform during these periods?
I tried to group the performance into general associations. The first group of five enjoyed periods of continued strength into the end of July or beginning of August before entering a downward phase lasting into mid-September and October. Only in 1988 did the rollover occur early and bottom at the end of August.
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The next group of five had sustained periods of weakness for June or mid-July, but this was followed by significant rallies where the June/July low reflected the absolute low for the following 6 months.
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And then there was the odd cases which didn't really fit any pattern (although 1976 could probably muscle into the 'June low and rally' group)
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So is there anything we can take from this?
Not really. There is nothing to suggest very light volume as part of a seasonal light trading period reflects underlying weakness. In the case of light June trading there is perhaps a greater case to be made in favour of a consolidation lasting to the end of June/mid-July before markets kick into a significant push higher - but it's a weak case.
However, with the exception of 2001, there was no strong evidence to a significant market meltdown and certainly no move which made a substantial undercut of June prices.
So, seller beware.
In my next article I will look at how the relative position of the S&P to its moving averages combined with light volume influence future price action.
Dr. Declan Fallon, Senior Market Technician, Zignals.com the free stock alerts, market alerts, and stock charts website