condition mean min max ZT0-3 7.411111110999999 7.411111110999999 7.411111110999999 ZT4-7 6.656111111333334 6.656111111333334 6.656111111333334 ZT8-11 6.742777778 6.742777778 6.742777778 ZT12-15 6.361111111 6.361111111 6.361111111 ZT16-19 4.914444444333333 4.914444444333333 4.914444444333333 ZT20-23 5.74 5.74 5.74