As I said, "more-or-less" self-supporting.
The WB finances about $40 billion in projects each year. The U.S. was to contribute $1.5 billion to all development banks combined, only one of which is the World Bank (I don't know its cut of the $1.5 billion).
I don't want to be in a position of defending the WB, just trying to clarify that much of its financial activity comes right back to America pockets. And that is a fact.