How to make a mirrored bar chart with amCharts5 XY column series stacked series

Question

I need a bar chart that comparatively displays two sets of data side by side along a horizontal axis.

So I have a stacked (but not clustered) column series XY chart (amCharts 5) which looks like this:

The plotted data is coming from an array of objects:

[
 {
  current: 61,
  previous: 29,
  ...
 },
 {
  current: 60,
  previous: 29,
  ...
 },
...
]

Now, how can I achieve this:

Do I need to find the average between current and previous then set that as a base, or do I really need negative values (say for previous) to achieve that? Either way, I was unable to make it look like above.

Found an example with amCharts4 but I don't understand how should I modify my chart to achieve the same mirror bar chart look.

I've put the chart together in a Codesandbox playground, I would appreciate some help. Data is hardcoded and there's an object with previous negative values aswell.

Answer 1

To do that, you need two vertical axes with opposite directions. They could be configured like so:

let yAxisCurrent = chart.yAxes.push(
  am5xy.ValueAxis.new(root, {
    renderer: am5xy.AxisRendererY.new(root, {}),
    calculateTotals: true,
    visible: true,
    min: 0
  })
);
  
let yAxisPrevious = chart.yAxes.push(
  am5xy.ValueAxis.new(root, {
    renderer: am5xy.AxisRendererY.new(root, {
      inversed: true // <--- DO NOT FORGET THIS
    }),
    calculateTotals: true,
    visible: true,
    min: 0
  })
);

Then add this line of code:

chart.leftAxesContainer.set("layout", root.verticalLayout);

Here is the result: https://codesandbox.io/s/sleepy-hooks-vwucth