CSS PROFILE - problem with a question

Paying for College
1

Hi!
I am currently filling in the CSS Profile and I have encountered a phrase that I do not understand. Here it is:

Enter the amount your parents paid for all taxes, mandatory withholdings, and set-asides during their country's most recent tax year. Include income taxes, state and local taxes, levies, and mandatory retirement payments. (Itemize the sources and amounts in Explanations/Special Circumstances (ES).)

I don’t understand the part in brackets.
What should I itemize?
Should I explain what kind of payments (taxes etc.) are included in the amount?

2

Itemize the different taxes that were paid, by type and amount, in section ES.

3

Thank you!
Btw, the word ‘sources’ is quite misleading, because you usually get money from a source, not deliver it to a source…

4

Think of it as the source of the tax bill.

5

That is very helpful, thank you again!