condition mean min max ZT0-3 2.1792800000000003 2.1792800000000003 2.1792800000000003 ZT4-7 0.953316 0.953316 0.953316 ZT8-11 1.7941799999999999 1.7941799999999999 1.7941799999999999 ZT12-15 1.96516 1.96516 1.96516 ZT16-19 4.138465 4.138465 4.138465 ZT20-23 2.594965 2.594965 2.594965