condition mean min max ZT0-3 5.38511 5.38511 5.38511 ZT4-7 3.8825849999999997 3.8825849999999997 3.8825849999999997 ZT8-11 2.96622 2.96622 2.96622 ZT12-15 3.242005 3.242005 3.242005 ZT16-19 4.66182 4.66182 4.66182 ZT20-23 3.8938699999999997 3.8938699999999997 3.8938699999999997