condition mean min max ZT0-3 6.7699025 6.126465 7.41334 ZT4-7 3.2764550000000003 3.2764550000000003 3.2764550000000003 ZT8-11 5.10998 5.10998 5.10998 ZT12-15 0 0 0 ZT16-19 2.067555 2.067555 2.067555 ZT20-23 2.7909249999999997 2.7909249999999997 2.7909249999999997