CountDemo.cs

private static void CountDemo(List<Order> orders)
{
    var march = new DateTime(2018, 3, 1);
    var ordersOnAndAfterMarch = orders.Where(order => order.OrderDate >= march);
    PrintOrders(ordersOnAndAfterMarch, indentBy: 4);
    var orderCountPlacedOnAndAfterMarch = orders.Count(order => order.OrderDate >= march);
    WriteLine($"Total Orders Placed On and After March: {orderCountPlacedOnAndAfterMarch}");
}