EW is a rather difficult thing to use at times as there can be a multitude of possibilities. Apart from that we had the heretofore unheard of flash-crash right in the middle to confuse matters even more. In constructing the proper count, that is the MOST plausible one AT THIS TIME, all the rules have to be adhered to with respect to overlap, size etc. etc. and comparisons with other indexes can be helpful.
The pattern leading to this latest down trend is a “expanding diagonal triangle” a.k.a a flag or pennant which has the very predictable attribute that it will be retraced in its entirety, that is to somewhere between 990 and 1010. (see green lines) The flash crash almost reached that point but not quite, assuring any observer that it was not just a flash in the pan due to thick fingers , but the real thing, that would still go lower. That almost certainly had to be a wave 3, the remaining question was of what degree. I have drawn 3 different counts that are plausible; in the red one wave 2 is an irregular flat: in the blue one the correction is quicker and the down trend is continued earlier, now in the 3d 1-2 ; in the purple one wave one down continues a lot longer and the wave 2, a zig-zag, is not at all complete as wave c of 2 can easily retrace 50 to 60% or more, 1125 is a minimum.
Which one is correct, if any , remains to be seen but for the bears the purple one will be the most frustrating – which is what is usually in store.