condition mean min max ZT0-3 95.939741 95.939741 95.939741 ZT4-7 81.1489255 81.1489255 81.1489255 ZT8-11 87.273833 87.273833 87.273833 ZT12-15 144.948894 144.948894 144.948894 ZT16-19 122.6363035 122.6363035 122.6363035 ZT20-23 276.3853035 276.3853035 276.3853035