var data = rSvc.getDashboardPayload(worklocation, property, year);

0:  {
month: 1
monthName: "Jan"
currentYearTarget: 100
currentYearActual: 90
}

var shwl = rSvc.getDashboardPayload(worklocation, BusinessRules.DataPropertyNames.SolidHazardousWasteLandfill, year);
var shwi = rSvc.getDashboardPayload(worklocation, BusinessRules.DataPropertyNames.SolidHazardousWasteIncineration, year);
var shmwr = rSvc.getDashboardPayload(worklocation, BusinessRules.DataPropertyNames.SolidHazardousMetallicWasteRecovery, year);
var shnmwr = rSvc.getDashboardPayload(worklocation, BusinessRules.DataPropertyNames.SolidHazardousNonMetallicWasteRecovery, year);

var merged = new List<WLDChartsPayload>(12);

for (short i = 1; i < 13; i++)
 {
   var m = new WLDChartsPayload();

   m.currentYearActual = shwl.Where(x => x.currentYearActual.HasValue && x.month == i).FirstOrDefault().currentYearActual;
   m.currentYearActual += shwi.Where(x => x.currentYearActual.HasValue && x.month == i).FirstOrDefault().currentYearActual;
   m.currentYearActual += shmwr.Where(x => x.currentYearActual.HasValue && x.month == i).FirstOrDefault().currentYearActual;
   m.currentYearActual += shnmwr.Where(x => x.currentYearActual.HasValue && x.month == i).FirstOrDefault().currentYearActual;

   m.currentYearTarget = shwl.Where(x => x.currentYearTarget.HasValue && x.month == i).FirstOrDefault().currentYearTarget;
   m.currentYearTarget += shwi.Where(x => x.currentYearTarget.HasValue && x.month == i).FirstOrDefault().currentYearTarget;
   m.currentYearTarget += shmwr.Where(x => x.currentYearTarget.HasValue && x.month == i).FirstOrDefault().currentYearTarget;
   m.currentYearTarget += shnmwr.Where(x => x.currentYearTarget.HasValue && x.month == i).FirstOrDefault().currentYearTarget;

   merged.Add(m);
 }