condition mean min max ZT0-3 41.492 37.217749999999995 45.76625 ZT4-7 31.460050000000003 31.460050000000003 31.460050000000003 ZT8-11 31.2388 31.2388 31.2388 ZT12-15 0 0 0 ZT16-19 36.99745 36.99745 36.99745 ZT20-23 33.222049999999996 33.222049999999996 33.222049999999996