condition mean min max ZT0-3 0.4495043333333334 0.4495043333333334 0.4495043333333334 ZT4-7 0.8875995 0.8875995 0.8875995 ZT8-11 2.3534450000000002 2.3534450000000002 2.3534450000000002 ZT12-15 2.93676 2.93676 2.93676 ZT16-19 3.57106 3.57106 3.57106 ZT20-23 2.4266900000000002 2.4266900000000002 2.4266900000000002