condition mean min max ZT0-3 5.18666 5.18666 5.18666 ZT4-7 3.66924 3.66924 3.66924 ZT8-11 2.57005 2.57005 2.57005 ZT12-15 3.409085 3.409085 3.409085 ZT16-19 6.48976 6.48976 6.48976 ZT20-23 5.80248 5.80248 5.80248