Williams Awesome Oscillator
The Williams AO is just a simple MACD 5, 34 of the midpoints of the price bars.
It is usually plotted with green bars when it is going up and red bars when it is going down.
|Only Plots Moving Down||
The Divide by 0 error in the Only Plots Moving Down formula is intentional. It makes it so the red bars do not plut when the AO is not moving down.