condition mean min max ZT0-3 21.227360460499998 7.360967691 35.09375323 ZT4-7 8.384776204 6.057479163 10.712073245 ZT8-11 13.2801529575 11.553635765 15.00667015 ZT12-15 10.87155665075 10.4905093455 11.252603956 ZT16-19 8.32253145675 7.1407602 9.5043027135 ZT20-23 12.21999432 11.23904628 13.200942359999999