how to count distinct values in excel for a matrix form - excel

Question

I have looked if this has been asked, but could not find out exactly.
I' ve been trying to count distinct values.
I tried sumproduct,sum(1/countif) etc, so far I got nothing but a div error or 0.
Basically, I' ve two columns: Campaign_no and customer_id.
what I need is count unique customers for each campaigns and count unique customers that appears in the campaigns at the same time, sort of matrix.
The table is as follows:
Campaign_no
Cust_id
A
1
A
2
A
2
B
1
B
4
B
5
B
9
C
4
C
5
C
6
C
7
What I need is below:
Campaigns
A
B
C
A
2
1
0
B
1
4
2
C
0
2
4
As you see Campaign A has 2 unique customers, so A-A cell is 2.
Campaign A and B have one customer in common, so A-B cell is 1.
Campaign A and C have no common customer, this box got 0.
Campaign B and C has 4 unique customer on their own,
but they have two common customers, so B-C box has 2 ( if those customers were the same, it would have been 1) .
Is there way of calculating this without vba or PT? I'm using Excel 2017.
Much appreciated.

Answer 1

Here is a solution using helper cells.
C2 is =A2&B2. Copy it to C3:C12.
D2 is =IF(ISNA(MATCH(B2,D1:$D$1,0)),B2,""). Copy it to D3:D12.
E2 is =IF($D2="","",1-ISNA(MATCH(E$1&$D2,$C$2:$C$12,0))). Copy it to E2:G12.
E15 is =SUMIFS($E$2:$E$12,E2:E12,1). Copy it to F15:G15.
E16 is =SUMIFS($F$2:$F$12,E2:E12,1). Copy it to F16:G16.
E17 is =SUMIFS($G$2:$G$12,E2:E12,1). Copy it to F17:G17.
You may be able to get away without using the helper column C in Office 2017. I only have Office 365, so I couldn't it correctly.

Answer 2

Here's one that you could try, but it assumes that the data is sorted into contiguous blocks in alphabetical order of campaign exactly as shown in the sample data:
=SUMPRODUCT((COUNTIFS($A$2:$A$12,F$1,$B$2:$B$12,INDEX($B$2:$B$12,MATCH($E2,$A$2:$A$12,0)):INDEX($B$2:$B$12,MATCH($E2,$A$2:$A$12,1)))>0)
/COUNTIFS($A$2:$A$12,$E2,$B$2:$B$12,INDEX($B$2:$B$12,MATCH($E2,$A$2:$A$12,0)):INDEX($B$2:$B$12,MATCH($E2,$A$2:$A$12,1))))
The idea is that you use countifs to check through each customer ID in campaign A (for example) to see if it's present in campaign B. But it's possible that a customer ID appears more than once in campaign A, so you still have to divide by the count of each customer number in campaign A to get the unique count.