or
var objectDataSource = new Telerik.Reporting.ObjectDataSource();objectDataSource.DataSource = GetData();var report = new Fuelomat.Reports.ConsumptionPerVehicleGroup();report.DataSource = objectDataSource;var reportSource = new InstanceReportSource {ReportDocument = report};ReportViewer.ReportSource = reportSource;ReportViewer.Visible = true;ChartMarkedZone mZone = new ChartMarkedZone();mZone.ValueStartY = 90;mZone.ValueEndY = 90;mZone.Appearance.Border.Color = Color.Red;mZone.Appearance.Border.Width = 2;chart_overzichtAantallen.PlotArea.MarkedZones.Add(mZone);