The profits are up more than $4 billion from last year, when the central bank made $34.2 billion.

The Fed's total income was $41.9 billion, most of which was from interest earned on United States government treasuries ($40.3 billion). Additional funds came from providing services to depository institutions ($878 billion) and earnings of foreign exchange and loans ($765 million).

After discounting for expenses and costs of the 12