condition mean min max ZT0-3 331.447051 331.447051 331.447051 ZT4-7 308.913013 308.913013 308.913013 ZT8-11 270.7815865 270.7815865 270.7815865 ZT12-15 342.1545065 342.1545065 342.1545065 ZT16-19 405.847226 405.847226 405.847226 ZT20-23 457.0953065 457.0953065 457.0953065