condition mean min max ZT0-3 0.9339116666666667 0.0987625 1.8403450000000001 ZT4-7 1.74481 1.74481 1.74481 ZT8-11 0.283516 0.283516 0.283516 ZT12-15 0.57930275 0.291589 0.8670165 ZT16-19 0.9051025 0.9051025 0.9051025 ZT20-23 0.409076 0.409076 0.409076