condition mean min max ZT0-3 24.315585 24.315585 24.315585 ZT4-7 28.905091 28.905091 28.905091 ZT8-11 31.7672715 31.7672715 31.7672715 ZT12-15 30.764364 30.764364 30.764364 ZT16-19 29.350597 29.350597 29.350597 ZT20-23 28.769246 28.769246 28.769246