<Tr> <Th> Census </Th> <Th> Pop . </Th> <Th> </Th> <Th>% ± </Th> </Tr> <Tr> <Td> 1970 </Td> <Td> 29,742 </Td> <Td> </Td> <Td>--</Td> </Tr> <Tr> <Td> 1980 </Td> <Td> 40,191 </Td> <Td> </Td> <Td> 35.1% </Td> </Tr> <Tr> <Td> </Td> <Td> 55,331 </Td> <Td> </Td> <Td> 37.7% </Td> </Tr>

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