condition mean min max ZT0-3 24.062989424999998 21.95104185 26.174937 ZT4-7 22.195826735 19.382542695 25.009110775 ZT8-11 14.68199676375 12.0683920925 17.295601435 ZT12-15 5.0231476315 4.4226029495 5.623692313499999 ZT16-19 10.0017452345 7.566324291 12.437166178 ZT20-23 16.4463282025 15.434626174999998 17.45803023