condition mean min max ZT0-3 2.5011202917500004 2.423412449 2.5788281345 ZT4-7 1.957126862 1.906763025 2.007490699 ZT8-11 1.81730810925 1.6777647130000002 1.9568515055 ZT12-15 2.771422008 2.2092997335 3.3335442824999997 ZT16-19 3.2209070445 2.6969906065 3.7448234825 ZT20-23 5.716028694499999 5.673965108999999 5.75809228