condition mean min max ZT0-3 5.341845 4.64135 6.686495 ZT4-7 9.200755000000001 9.200755000000001 9.200755000000001 ZT8-11 9.24347 9.24347 9.24347 ZT12-15 9.858509999999999 9.31657 10.40045 ZT16-19 8.55684 8.55684 8.55684 ZT20-23 6.759790000000001 6.759790000000001 6.759790000000001