condition mean min max ZT0-3 3.2036249999999997 3.2036249999999997 3.2036249999999997 ZT4-7 2.7164900000000003 2.7164900000000003 2.7164900000000003 ZT8-11 2.76812 2.76812 2.76812 ZT12-15 2.6775599999999997 2.6775599999999997 2.6775599999999997 ZT16-19 3.47594 3.47594 3.47594 ZT20-23 2.946815 2.946815 2.946815