condition mean min max ZT0-3 35.9691 35.9691 35.9691 ZT4-7 25.1477 25.1477 25.1477 ZT8-11 29.6724 29.6724 29.6724 ZT12-15 30.50375 30.50375 30.50375 ZT16-19 36.96055 36.96055 36.96055 ZT20-23 35.633750000000006 35.633750000000006 35.633750000000006