condition mean min max ZT0-3 4.10701503925 3.516475307 4.6975547715 ZT4-7 4.7428268755000005 4.7227991970000005 4.762854554 ZT8-11 3.46630424375 3.4583036550000004 3.4743048324999997 ZT12-15 4.01789361475 3.3823790170000003 4.6534082125000005 ZT16-19 4.46034427275 3.7346721054999996 5.1860164399999995 ZT20-23 9.670925993500001 8.230222632 11.111629355000002