condition mean min max ZT0-3 4.429938333333333 3.6135650000000004 5.696455 ZT4-7 3.445605 3.445605 3.445605 ZT8-11 5.336375 5.336375 5.336375 ZT12-15 4.0529399999999995 2.835655 5.270225 ZT16-19 2.770085 2.770085 2.770085 ZT20-23 8.3655 8.3655 8.3655