Count of undelivered orders

[Vinni2000]

I have orders data like this

Order_number.    Item_number.    Delivery_status

1011.                                 1.                          Delivered

1011.                                  2.                          Undelivered

1012.                                  1.                           Delivered

1013.                                  1.                            Delivered 

So here I want the count of orders that are undelivered , here we have 2 items in one order so the thing is we consider order is delivered even if one item is delivered , we want this at order level not at item level 

[BrunPierre]

Perhaps?

=Count(DISTINCT {<Order_number=P({1<Delivery_status={'Delivered'}>})>} Order_number)

[Vinni2000]

Not it's giving the count of orders that are delivered but we want undelivered count 

[BrunPierre]

Hi, from your explanation, the output for the above sample will read zero count.

=Count(DISTINCT {<Order_number=E({1<Delivery_status={'Delivered'}>})>} Order_number)