condition mean min max ZT0-3 20.397075 20.3947 20.39945 ZT4-7 15.2746 15.2746 15.2746 ZT8-11 38.29885 38.29885 38.29885 ZT12-15 0 0 0 ZT16-19 44.09325 44.09325 44.09325 ZT20-23 35.25875 35.25875 35.25875