condition mean min max ZT0-3 18.3479 18.3479 18.3479 ZT4-7 16.28485 16.28485 16.28485 ZT8-11 15.0433 15.0433 15.0433 ZT12-15 16.82045 16.82045 16.82045 ZT16-19 20.75885 20.75885 20.75885 ZT20-23 18.479750000000003 18.479750000000003 18.479750000000003