S&P500 has turned down yesterday from 4453 lvl., near the area of Fib. ratio of 0.382 and 0.50. Also the lower parallel channel line reacted as resistance (orange). Further bearish, impulsive move below the former swing low at 4287 would indicate a completed wave (4), and wave (5) to be underway, targeting 4211/4160 area in a five-wave sub-structure.