<Tr> <Th> Opened </Th> <Td> 1987; 30 years ago (1987) </Td> </Tr> <Tr> <Th> Hub for </Th> <Td> <Ul> <Li> BA CityFlyer </Li> <Li> Flybe </Li> </Ul> </Td> </Tr> <Ul> <Li> BA CityFlyer </Li> <Li> Flybe </Li> </Ul> <Tr> <Th> Elevation AMSL </Th> <Td> 19 ft / 6 m </Td> </Tr>

How many flights per day from london city airport