using the IOrderSearchService we run reports for specific time periods and during some of those time periods we have sales and if the cart total is above 200 the customer gets free shipping.

We've noticed sometimes that the Total Revenue is sometimes less than the sub total.  Does anyone know how that's possible?

code snippet below

var orderFilter = new OrderSearchFilter
{
CreatedFrom = data.StartDate,
CreatedTo = data.EndDate.AddDays(1)
};


var orderSearchService = ServiceLocator.Current.GetInstance<IOrderSearchService>();
var searchResult = orderSearchService.FindPurchaseOrders(orderFilter);
completedTotalRev = searchResult.Orders.Sum(x => x.GetTotal()); //Sometimes lower than completedSubTotal
completedSubTotal = searchResult.Orders.Sum(x => x.GetSubTotal());

Thank you
Commerce 13.32.6.0