condition mean min max ZT0-3 28.963601 28.963601 28.963601 ZT4-7 32.586008 32.586008 32.586008 ZT8-11 32.560164 32.560164 32.560164 ZT12-15 35.7266645 35.7266645 35.7266645 ZT16-19 37.199603499999995 37.199603499999995 37.199603499999995 ZT20-23 42.1343095 42.1343095 42.1343095