condition mean min max ZT0-3 3.3535193019999996 2.0234382909999997 4.6836003129999995 ZT4-7 7.41487967575 5.8667627595 8.962996592 ZT8-11 22.01811539025 11.8673311355 32.168899644999996 ZT12-15 59.1991141525 55.10864222 63.289586084999996 ZT16-19 52.416714372499996 51.663901515 53.16952723 ZT20-23 62.574170735 61.401616765 63.746724705000005