<Tr> <Th> City </Th> <Td> 3,711,930 </Td> </Tr> <Tr> <Th> Density </Th> <Td> 4,200 / km (11,000 / sq mi) </Td> </Tr> <Tr> <Th> Metro </Th> <Td> 6,004,857 </Td> </Tr> <Tr> <Th> Demonym (s) </Th> <Td> Berliner (m), Berlinerin (f) </Td> </Tr>

When did berlin become the capital of germany