<Tr> <Td> 1963--1984 (21 years) </Td> <Td> Jim Brown </Td> <Td> Cleveland Browns (1957--1965) </Td> <Td> 2,359 </Td> <Td> 12,312 </Td> <Td> 5.2 </Td> </Tr> <Tr> <Td> 1984--2002 (18 years) </Td> <Td> Walter Payton </Td> <Td> Chicago Bears (1975--1987) </Td> <Td> 3,838 </Td> <Td> 16,726 </Td> <Td> 4.4 </Td> </Tr> <Tr> <Td> Since 2002 (15 years) </Td> <Td> Smith, Emmitt Emmitt Smith </Td> <Td> Dallas Cowboys (1990--2002) Arizona Cardinals (2003--2004) </Td> <Td> 4,409 </Td> <Td> 18,355 </Td> <Td> 4.2 </Td> </Tr>

Who has the most yards in the nfl
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