condition mean min max ZT0-3 67.617106 67.617106 67.617106 ZT4-7 47.2821455 47.2821455 47.2821455 ZT8-11 55.052525 55.052525 55.052525 ZT12-15 58.990857500000004 58.990857500000004 58.990857500000004 ZT16-19 33.7180535 33.7180535 33.7180535 ZT20-23 18.64906 18.64906 18.64906