Hi Sharvari
Source structure are basically used for co-products scenario where common cost are allocated to receivers...in normal settlement profile this is not required at all.
Suppose you have Electricity cost 500
Water cost 400
Travelling cost 600
You have 2 co-products P1 & P2 in that case you can allocate cost through source structure
Elect 250 P1 50%
250 P2 50%
Like this ...so basic logic is common cost to be allocated to receivers as per source structure
Kamal