Transfers of income means to move money from one place to another, so in this context I believe it is referring to the amount of money being transferred within the government.

'Transfers of Income' is a slighly strange and imprecise phrase, but I guess it means government provides either services or funds; funds given to external bodies, charities, quasi-government organisations... these are fundings that may have been termed 'transfers of income' but i'd prefer 'external fundings'