condition mean min max ZT0-3 27.445022 27.445022 27.445022 ZT4-7 27.220588999999997 27.220588999999997 27.220588999999997 ZT8-11 24.053231500000003 24.053231500000003 24.053231500000003 ZT12-15 23.107228 23.107228 23.107228 ZT16-19 25.5166075 25.5166075 25.5166075 ZT20-23 22.6939385 22.6939385 22.6939385