Futures have been hit fairly hard in Globex. Cash-based internals are very compressed and suggest a low should occur soon. That is a time call, not a price call. We may be in the midst of a short-term capitulation phase when prices drop dramatically in a short time before attempting a retracement. In the S&P cash, 1550-1530 is a strong candidate to contain immediate selling and from where the S&P may attempt to bottom.

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S&P Daily Cash