public class CIMChartHistogramSeries : CIMChartSeries, System.ComponentModel.INotifyPropertyChanged, System.Xml.Serialization.IXmlSerializable  

{
  // For more information on the chart CIM specification:
  // https://github.com/Esri/cim-spec/blob/main/docs/v3/CIMCharts.md

  var lyrDefHistogram = featureLayer.GetDefinition();

  // Get list names for fields of type Double
  var doubleFields = featureLayer.GetFieldDescriptions().Where(f => f.Type == FieldType.Double).Select(f => f.Name);

  // Create list that will contain all histograms
  var histograms = new List<CIMChart>();

  // Create histogram for each Double field
  foreach (var field in doubleFields)
  {
    // Define histogram CIM properties
    var histogram = new CIMChart
    {
      Name = $"histogram_{field}",
      GeneralProperties = new CIMChartGeneralProperties
      {
        Title = $"Histogram for {field}",
        UseAutomaticTitle = false
      },
      Series =
        [
              new CIMChartHistogramSeries {
                  UniqueName = "histogramSeries",
                  Name = $"histogram_{field}",
                  BinCount = 15,
                  // Specify the number field
                  Fields = new string[] { field },
              }
        ]
    };


    histograms.Add(histogram);
  }
  ;

  // Add new chart to layer's existing list of charts (if any exist)
  var allChartsHistogram = (lyrDefHistogram == null) ? histograms : lyrDefHistogram.Charts.Concat(histograms);
  // Add CIM chart to layer definition 
  lyrDefHistogram.Charts = allChartsHistogram.ToArray();
  featureLayer.SetDefinition(lyrDefHistogram);
}