condition mean min max ZT0-3 28.553916666666666 16.5796 36.662949999999995 ZT4-7 12.328975 12.328975 12.328975 ZT8-11 23.43095 23.43095 23.43095 ZT12-15 23.035050000000002 19.223100000000002 26.847 ZT16-19 12.5962 12.5962 12.5962 ZT20-23 19.25505 19.25505 19.25505