condition mean min max ZT0-3 10.577694 10.577694 10.577694 ZT4-7 12.0934235 12.0934235 12.0934235 ZT8-11 9.268143 9.268143 9.268143 ZT12-15 19.175264499999997 19.175264499999997 19.175264499999997 ZT16-19 10.021618499999999 10.021618499999999 10.021618499999999 ZT20-23 15.8475155 15.8475155 15.8475155