condition mean min max ZT0-3 3.33526 2.5304399999999996 4.14008 ZT4-7 3.753152 3.753152 3.753152 ZT8-11 6.342005 6.342005 6.342005 ZT12-15 0 0 0 ZT16-19 9.021609999999999 9.021609999999999 9.021609999999999 ZT20-23 9.44568 9.44568 9.44568