condition mean min max ZT0-3 3.8133266666666668 3.136675 4.681675 ZT4-7 3.82148 3.82148 3.82148 ZT8-11 3.0534350000000003 3.0534350000000003 3.0534350000000003 ZT12-15 3.0406225 2.738785 3.34246 ZT16-19 3.0789850000000003 3.0789850000000003 3.0789850000000003 ZT20-23 7.296474999999999 7.296474999999999 7.296474999999999