condition mean min max ZT0-3 31.049999999999997 31.049999999999997 31.049999999999997 ZT4-7 9.7 9.7 9.7 ZT8-11 38.599999999999994 38.599999999999994 38.599999999999994 ZT12-15 18.75 18.75 18.75 ZT16-19 26.35 26.35 26.35 ZT20-23 36.900000000000006 36.900000000000006 36.900000000000006