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Here we see an interesting dynamic of recent markets: rising prices in SPY (blue line) have been associated with lower average volume (top chart) and reduced average daily ranges (bottom chart).
Coming up to a Fed announcement, we may see further slow, range trade. Note that, over the last ten trading sessions, SPY has had a daily trading range greater than 1% on only one occasion--and that was only about 1.1%.
Adjusting to these changing volatility expectations has been a major challenge for intraday traders. This is why I find volatility-adjusted price targets, such as those posted via Twitter each morning, so helpful: they temper my expectations on the day.
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