Link to script at bottom
Use OBV/Price to see a price adjusted by 'On Balance Volume' - (OBV), a that measures positive and negative flow, was developed by Joseph Granville and introduced in 1963.
The indicator, together with , provides good entry/ exit points.
In the chart note the exit point before the crash.
Also, note the "wedge" - a bit lees optimistic that the 'price only' for SPY .