condition mean min max ZT0-3 60.461389 60.461389 60.461389 ZT4-7 68.8686975 68.8686975 68.8686975 ZT8-11 68.82829849999999 68.82829849999999 68.82829849999999 ZT12-15 68.45312 68.45312 68.45312 ZT16-19 83.439196 83.439196 83.439196 ZT20-23 80.2972595 80.2972595 80.2972595