condition mean min max ZT0-3 2.5440391462500003 2.335751592 2.7523267005000003 ZT4-7 4.10519900025 2.4134742385 5.7969237620000005 ZT8-11 5.346670818500001 5.1571301730000005 5.536211464000001 ZT12-15 5.05745158125 4.3909295455 5.723973617 ZT16-19 8.700346090750001 8.611161687500001 8.789530494000001 ZT20-23 6.88730623975 5.8911911275 7.883421351999999