<Table> UN (medium variant--2012 revision) and US Census Bureau (June 2015) estimates <Tr> <Th> Year </Th> <Th> UN est . (millions) </Th> <Th> Difference </Th> <Th> USCB est . (millions) </Th> <Th> Difference </Th> </Tr> <Tr> <Th> 2005 </Th> <Td> 6,514 </Td> <Td>--</Td> <Td> 6,473 </Td> <Td>--</Td> </Tr> <Tr> <Th> </Th> <Td> 6,916 </Td> <Td> 402 </Td> <Td> 6,866 </Td> <Td> 393 </Td> </Tr> <Tr> <Th> 2015 </Th> <Td> 7,324 </Td> <Td> 408 </Td> <Td> 7,256 </Td> <Td> 390 </Td> </Tr> <Tr> <Th> 2020 </Th> <Td> 7,717 </Td> <Td> 393 </Td> <Td> 7,643 </Td> <Td> 380 </Td> </Tr> <Tr> <Th> 2025 </Th> <Td> 8,083 </Td> <Td> 366 </Td> <Td> 8,007 </Td> <Td> 363 </Td> </Tr> <Tr> <Th> 2030 </Th> <Td> 8,425 </Td> <Td> 342 </Td> <Td> 8,341 </Td> <Td> 334 </Td> </Tr> <Tr> <Th> 2035 </Th> <Td> 8,743 </Td> <Td> 318 </Td> <Td> 8,646 </Td> <Td> 306 </Td> </Tr> <Tr> <Th> 2040 </Th> <Td> 9,039 </Td> <Td> 296 </Td> <Td> 8,926 </Td> <Td> 280 </Td> </Tr> <Tr> <Th> 2045 </Th> <Td> 9,308 </Td> <Td> 269 </Td> <Td> 9,180 </Td> <Td> 254 </Td> </Tr> <Tr> <Th> 2050 </Th> <Td> 9,551 </Td> <Td> 243 </Td> <Td> 9,408 </Td> <Td> 228 </Td> </Tr> </Table> <Tr> <Th> Year </Th> <Th> UN est . (millions) </Th> <Th> Difference </Th> <Th> USCB est . (millions) </Th> <Th> Difference </Th> </Tr> <Tr> <Th> 2005 </Th> <Td> 6,514 </Td> <Td>--</Td> <Td> 6,473 </Td> <Td>--</Td> </Tr> <Tr> <Th> </Th> <Td> 6,916 </Td> <Td> 402 </Td> <Td> 6,866 </Td> <Td> 393 </Td> </Tr>

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