condition mean min max ZT0-3 6.099775 5.70032 6.499230000000001 ZT4-7 3.82544 3.82544 3.82544 ZT8-11 4.14179 4.14179 4.14179 ZT12-15 0 0 0 ZT16-19 4.872095 4.872095 4.872095 ZT20-23 5.6186 5.6186 5.6186