condition mean min max ZT0-3 88.165325 82.34 93.99065 ZT4-7 78.21105 78.21105 78.21105 ZT8-11 85.54885 85.54885 85.54885 ZT12-15 0 0 0 ZT16-19 78.70355 78.70355 78.70355 ZT20-23 92.5976 92.5976 92.5976