void StatisticsViewModel_FilterTypeChanged(object sender, PeriodEventArgs e)
        {
            var addresses = new HashSet <Address>(QueriesHelper.GetDistinctStoresForPeriod(UnitOfWork.Orders, PrimaryKey).Where(x => x != null).Select(cs => cs.Address));

            this.CitiesMapViewModel.Cities = CreateCities(addresses, e.Period);
        }
        void StatisticsViewModel_FilterTypeChanged(object sender, PeriodEventArgs e)
        {
            var addresses = new HashSet <Address>(GetSalesStores().Select(cs => cs.Address));

            this.CitiesMapViewModel.Cities = CreateCities(addresses, e.Period);
        }