condition mean min max ZT0-3 25.002766666666666 16.509149999999998 29.5669 ZT4-7 15.79505 15.79505 15.79505 ZT8-11 17.65235 17.65235 17.65235 ZT12-15 23.38825 22.47365 24.30285 ZT16-19 25.026699999999998 25.026699999999998 25.026699999999998 ZT20-23 29.0938 29.0938 29.0938