With just the info you have provided I would guess that someone is expecting you
to take a bunch of raw data, much like a dump out of a mainframe, or database,
and then summarise that data in a nice friendly manner such as Excel's Pivot
tables will do for you, eg:-
A B
1 Code Val
2 b 3
3 a 1
4 c 2
5 c 2
6 b 3
7 a 1
8 b 1
9 a 4
One example of a summary of the above would be
D E
1 Code Sum of Val
2 a 6
3 b 7
4 c 4
This is all achieved automatically by using something like a Pivot table
though, and you don't do it all manually
As to the structure diagram, hard to say without more info and an example of
your data.