<Tr> <Td> </Td> <Td> Refined petroleum </Td> <Td> 51,929 </Td> </Tr> <Tr> <Td> </Td> <Td> Planes, helicopters, and spacecraft </Td> <Td> 39,630 </Td> </Tr> <Tr> <Td> </Td> <Td> Pharmaceuticals </Td> <Td> 37,876 </Td> </Tr> <Tr> <Td> </Td> <Td> Gas turbines </Td> <Td> 28,953 </Td> </Tr>

What item is especially popular as an export to the united states