The NYSE TICK gives a reading of intraday sentiment, as it shows the number of stocks trading on upticks minus those trading on downticks. Since it takes program trades to move stocks up or down in unison, very high or very low readings of NYSE TICK provide a tell as to the directional bias of such programs. Note that, to this point today, we've had only two readings above +800, but many more below -800. We can also see that TICK has spent more time below the horizontal blue zero line than above. When you combine those observations with this morning's intermarket themes (weak commodities, strong dollar), you can see why it has made sense to lean toward the sell side in stocks.
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