For reference, from the 2019/20 TFL Budget, direct operating surplus' are:

Streets -£167m

Buses: -£722m

Rail: -£49m

Underground: £823m

Elizabeth Line: -£267m

Other: £9m

Professional Services: -£560m

Property: £69m

Media: £145m

[0] http://content.tfl.gov.uk/tfl-budget-2019-20.pdf