<BarChart
  xAxis={[
    {
      scaleType: 'band',
      dataKey: 'code',
      valueFormatter: (code, context) =>
        context.location === 'tick'
          ? code
          : `Country: ${dataset.find((d) => d.code === code)?.name} (${code})`,
    },
  ]}
  {...chartParams}
/>