A Donut Series has all the benefits of a Pie Series and allows displaying multiple datasets in a single chart.
 Simple Donut Copy Link  
To create a Donut Series, use the donut series type.
{
    series: [
        {
            type: 'donut',
            calloutLabelKey: 'asset',
            angleKey: 'amount',
        },
    ],
}
An optional innerRadiusRatio can be provided which should be a value between 0 and 1 and defines the radius of the inner circle as a ratio of the outer radius of the chart.
 Inner Labels Copy Link  
The innerLabels property can be used to put several lines of text in the space inside a Donut Series.
The colour of the centre area can be changed by using innerCircle.
{
    series: [
        {
            // ...
            innerLabels: [
                {
                    text: 'Total Investment',
                    fontWeight: 'bold',
                },
                {
                    text: '$100,000',
                    spacing: 4,
                    fontSize: 44,
                    color: 'green',
                },
            ],
            innerCircle: {
                fill: '#c9fdc9',
            },
        },
    ],
}
 Multiple Donuts Copy Link  
To render multiple Donut Series in a single chart without overlapping, set an outerRadiusRatio in conjunction with an innerRadiusRatio.
{
    series: [
        {
            // outer series
            // ...
            outerRadiusRatio: 1, // the default
            innerRadiusRatio: 0.9,
            title: { text: 'Previous Year', showInLegend: true },
        },
        {
            // inner series
            // ...
            outerRadiusRatio: 0.6,
            innerRadiusRatio: 0.2,
            title: { text: 'Current Year', showInLegend: true },
        },
    ],
}
In the above configuration:
- The difference of 
0.3between theinnerRadiusRatioof the outer series and theouterRadiusRatioof the inner series determines the size of the gap between the outer and inner series. - The difference between 
outerRadiusRatioandinnerRadiusRatiofor each series determines the thickness of the ring for that series. - The 
titleprovided for each series is displayed above the Donut Series if there is space. - Using 
showInLegenddisplays the title within the legend item, allowing differentiation between the two series within the legend. 
 Shared Legend Copy Link  
 Providing a matching legendItemKey allows synchronising of legend items across multiple Donut Series. When a legend item is clicked, all items with a matching legendItemKey are toggled.
{
    series: [
        {
            // ...
            calloutLabelKey: 'asset',
            legendItemKey: 'asset',
        },
        {
            // ...
            legendItemKey: 'asset',
            showInLegend: false,
        },
    ],
}
Using showInLegend: false for the second series, ensures that there are no duplicate legend items.