condition mean min max ZT0-3 15.0535 15.0535 15.0535 ZT4-7 9.148484999999999 9.148484999999999 9.148484999999999 ZT8-11 7.7084399999999995 7.7084399999999995 7.7084399999999995 ZT12-15 25.773249999999997 25.773249999999997 25.773249999999997 ZT16-19 44.73309999999999 44.73309999999999 44.73309999999999 ZT20-23 30.3177 30.3177 30.3177