condition mean min max ZT0-3 12.699876 12.699876 12.699876 ZT4-7 12.5168435 12.5168435 12.5168435 ZT8-11 11.0519415 11.0519415 11.0519415 ZT12-15 12.298321 12.298321 12.298321 ZT16-19 11.267908 11.267908 11.267908 ZT20-23 11.539926999999999 11.539926999999999 11.539926999999999