SPX - Half Way There

This is a re-post of a chart from one month ago after the dow dropped 700 points in one day. My extrapolation from that post compared this to 1987, in which there was a 2 year run up, and then a quick crash which erased 1 years worth of gains.
While this 2018 crash appears to be slower in time than 1987's two month crash period, the charts nonetheless look the same to me. If we extrapolate, then SPX's current price has only reached half way to where it will eventually bottom out, which should be around 2380.