Watch out for that std dev. Way too off from norm. spy is stretched from 157.50 to this level. That means, if market comes back to 157.50 it will be at unacceptable std deviation for more selloff.
i.e even if market selloffs to spy 157.50 we are still away 2sigma from mean, so this rally from spy 157.50 is an outlier not sustainable statistically.