condition mean min max ZT0-3 498.191492 498.191492 498.191492 ZT4-7 508.76765049999995 508.76765049999995 508.76765049999995 ZT8-11 498.51147149999997 498.51147149999997 498.51147149999997 ZT12-15 541.2201745 541.2201745 541.2201745 ZT16-19 642.4726785 642.4726785 642.4726785 ZT20-23 612.5398625 612.5398625 612.5398625