Extra spacing around SfCircularChart

first time asking a question here. I would like to how to remove the extra spacing around the SfCircularChart from syncfusion_flutter_charts package.

Container(
 // Wrapping around fixed size Container
 width: 200,
 height: 200,
 color: Colors.red,
 child: SfCircularChart(
  // Setting the margin to zero
  margin: EdgeInsets.zero,
  series: <CircularSeries>[
   PieSeries<Category, String>(
    dataSource: dailyEarningList,
    xValueMapper: (Category data, _) => data.name,
    yValueMapper: (Category data, _) => data.value,
    dataLabelSettings: DataLabelSettings(
     isVisible: true,
    ),
   ),
  ],
 ),
)

Image

PieSeries<Category, String>(
            radius: "100",
            dataSource: [Category(["a", "b", "c"])],
            xValueMapper: (Category data, _) => "d",
            yValueMapper: (Category data, _) => 1,
            dataLabelSettings: const DataLabelSettings(
              isVisible: true,
            ),
          ),

The library has a radius parameter. It's a string. I do not understand why it's a string. In your example if you set it to "100", it will match the container.