If we look, not at median high/low ranges, but at median open to close changes, those numbers become even more stark. The median open to close change during the first half hour of trade is only .29%. That dwindles to .11% during midday hours. The fact that open to close changes are only about half those of high/low ranges, tells you that, even during 30-minute market periods, there is considerable choppiness.
The figures can also be useful for telling you when there is enough movement and opportunity to trade--and when you might want to stand aside and wait for broader market participation and movement. A savvy reader will integrate the post on volume norms with the recent post on what moves markets and realize that the shifting volume numbers reflect *who* is dominating market action at different times of day.
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When to Not Trade
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When to Not Trade