condition mean min max ZT0-3 4.80091 3.723125 5.619515 ZT4-7 3.092085 3.092085 3.092085 ZT8-11 4.675565 4.675565 4.675565 ZT12-15 4.94674 4.814555 5.078925 ZT16-19 5.082715 5.082715 5.082715 ZT20-23 7.38111 7.38111 7.38111