private void PopulateSimulationData()
 {
     for (int i = 0; i < DURATION; i++)
     {
         float value = (float)SimulationFunction(i);
         ObsCollection.Add(new KeyValuePair <long, float>(i, value));
     }
 }
 public MainWindowVM()
 {
     _Data = new ObsCollection(NotifyTotalSalaryChanged);
     LoadData();
 }