/// <summary>
        /// Adds engine average consumption refference line.
        /// </summary>
        /// <param name="helper"></param>
        private void AddEnginesConsumptionTrendline(FusionChartsMultiSeriesHelper helper)
        {
            var trendline = new FusionChartsTrendline();

            var avgConsumption = (from nivel in ReportObjectsList select nivel.Consumo).Average();

            trendline.AddPropertyValue("startValue", string.Format("{0}", (int)avgConsumption));
            trendline.AddPropertyValue("displayValue", string.Format("{0}: {1}lit", CultureManager.GetLabel("CONSUMO"), (int)avgConsumption));
            trendline.AddPropertyValue("color", HexColorUtil.ColorToHex(Color.LightCoral));
            trendline.AddPropertyValue("thickness", "3");

            helper.AddTrendLine(trendline);
        }