condition mean min max ZT0-3 1.9136275 1.630915 2.19634 ZT4-7 3.8749350000000002 3.8749350000000002 3.8749350000000002 ZT8-11 3.8446 3.8446 3.8446 ZT12-15 0 0 0 ZT16-19 2.158455 2.158455 2.158455 ZT20-23 1.624725 1.624725 1.624725