<Tr> <Th> Billions </Th> <Th> Adjusted </Th> <Th> Change </Th> <Th> Billions </Th> <Th> Adjusted </Th> <Th> Change </Th> <Th> Billions </Th> <Th> Adjusted </Th> <Th> Change </Th> </Tr> <Tr> <Td> 1977 </Td> <Td> $409 </Td> <Td> $1,040 </Td> <Td> </Td> <Td> $705 </Td> <Td> $1,795 </Td> <Td> </Td> <Td> $1,974 </Td> <Td> $5,019 </Td> <Td> </Td> <Td> 0.39 </Td> </Tr> <Tr> <Td> 1978 </Td> <Td> $459 </Td> <Td> $1,093 </Td> <Td> 5.1% </Td> <Td> $776 </Td> <Td> $1,850 </Td> <Td> 3.1% </Td> <Td> $2,217 </Td> <Td> $5,285 </Td> <Td> 5.3% </Td> <Td> 0.42 </Td> </Tr> <Tr> <Td> 1979 </Td> <Td> $504 </Td> <Td> $1,107 </Td> <Td> 1.3% </Td> <Td> $829 </Td> <Td> $1,821 </Td> <Td> − 1.5% </Td> <Td> $2,501 </Td> <Td> $5,494 </Td> <Td> 4.0% </Td> <Td> 0.46 </Td> </Tr>

When did the us debt reach 1 trillion