condition mean min max ZT0-3 163.509012 163.509012 163.509012 ZT4-7 362.870062 362.870062 362.870062 ZT8-11 193.49182150000001 193.49182150000001 193.49182150000001 ZT12-15 194.5927165 194.5927165 194.5927165 ZT16-19 274.013588 274.013588 274.013588 ZT20-23 211.399884 211.399884 211.399884