condition mean min max ZT0-3 2533.039749 2533.039749 2533.039749 ZT4-7 808.2710685 808.2710685 808.2710685 ZT8-11 677.7367999999999 677.7367999999999 677.7367999999999 ZT12-15 711.0213145 711.0213145 711.0213145 ZT16-19 1111.096746 1111.096746 1111.096746 ZT20-23 1168.176403 1168.176403 1168.176403