condition mean min max ZT0-3 1.80594 1.80594 1.80594 ZT4-7 2.278805 2.278805 2.278805 ZT8-11 0.776403 0.776403 0.776403 ZT12-15 0.46829350000000003 0.46829350000000003 0.46829350000000003 ZT16-19 1.867665 1.867665 1.867665 ZT20-23 2.4655 2.4655 2.4655