condition mean min max ZT0-3 384.941816 384.941816 384.941816 ZT4-7 259.7740635 259.7740635 259.7740635 ZT8-11 313.92431899999997 313.92431899999997 313.92431899999997 ZT12-15 371.12611200000003 371.12611200000003 371.12611200000003 ZT16-19 570.7061315 570.7061315 570.7061315 ZT20-23 581.037814 581.037814 581.037814