condition mean min max ZT0-3 0.3244278333333333 0.1466765 0.46394799999999997 ZT4-7 1.1434625 1.1434625 1.1434625 ZT8-11 2.28176 2.28176 2.28176 ZT12-15 2.9673425 2.20344 3.7312450000000004 ZT16-19 1.607785 1.607785 1.607785 ZT20-23 1.66161 1.66161 1.66161