condition mean min max ZT0-3 6.614718333333333 3.74874 10.004249999999999 ZT4-7 6.392799999999999 6.392799999999999 6.392799999999999 ZT8-11 2.2156089999999997 2.2156089999999997 2.2156089999999997 ZT12-15 13.06426 4.27257 21.85595 ZT16-19 20.2935 20.2935 20.2935 ZT20-23 7.22041 7.22041 7.22041