condition mean min max ZT0-3 19.058500000000002 17.288800000000002 20.8282 ZT4-7 17.96425 17.96425 17.96425 ZT8-11 24.20615 24.20615 24.20615 ZT12-15 0 0 0 ZT16-19 22.279449999999997 22.279449999999997 22.279449999999997 ZT20-23 21.32445 21.32445 21.32445