condition mean min max ZT0-3 9.495475 9.495475 9.495475 ZT4-7 10.269338999999999 10.269338999999999 10.269338999999999 ZT8-11 11.374964 11.374964 11.374964 ZT12-15 10.9706375 10.9706375 10.9706375 ZT16-19 14.7510145 14.7510145 14.7510145 ZT20-23 18.7198545 18.7198545 18.7198545