private void GetSalesReport()
{
SalesDataCollection = _objDashboardManager.GetProductSales().ToObservableCollection();
YearCollection = SalesDataCollection.GroupBy(x => x.Year).Select(m => m.First()).ToObservableCollection();
CountryCollection = SalesDataCollection.GroupBy(x => x.Country).Select(m => m.First()).ToObservableCollection();
}