How to create a bar graph with the same pseudo-variable appearing twice in the same table

[#1]

Hi, I have this problem:

I have a set of data with 2 variables IN and OUT, and their respective counters:

Table1:
LOAD * INLINE [   
ID, IN, OUT, COUNTIN, COUNTOUT   
1, , A, 0, 1
2, A, A, 1, 1
3, , B, 0, 1
4, B, B, 1, 1
5, A, C, 1, 1
6, , A, 0, 1
7, , C, 0, 1
8, C, C, 1, 1
9, A, A, 1, 1
10, A, B, 1, 1
11, , C, 0, 1
12, B, D, 1, 1
];

I'd like to have a bar graph containing the proportion between the number of occurences of each group in IN and the number of occurences of this same group in OUT.
The dimension would be the group. So, the answer would be

A = 4/4
B = 2/3
C = 1/4

How can I make this?

Thanks in advance.

[Nicole-Smith]

See the load script and chart in the attached.

[maxgro · Accepted solution]

this is my result, see atacchment for details