condition mean min max ZT0-3 4.053075 3.530355 4.575794999999999 ZT4-7 3.1561250000000003 3.1561250000000003 3.1561250000000003 ZT8-11 1.9956049999999999 1.9956049999999999 1.9956049999999999 ZT12-15 0 0 0 ZT16-19 5.197725 5.197725 5.197725 ZT20-23 4.65855 4.65855 4.65855