<Tr> <Td> Special Drawing Rights Certificate Acct . </Td> <Td> </Td> <Td> 5.20 </Td> </Tr> <Tr> <Td> Treasury Currency Outstanding (Coin) </Td> <Td> </Td> <Td> 43.98 </Td> </Tr> <Tr> <Td> Securities Held Outright </Td> <Td> </Td> <Td> 2647.94 </Td> </Tr> <Tr> <Td> U.S. Treasury Securities </Td> <Td> </Td> <Td> 1623.78 </Td> </Tr>

What are the principal taxes that exist in the united states today