condition mean min max ZT0-3 18.34365 18.34365 18.34365 ZT4-7 12.9198 12.9198 12.9198 ZT8-11 9.31578 9.31578 9.31578 ZT12-15 12.377875 12.377875 12.377875 ZT16-19 12.20495 12.20495 12.20495 ZT20-23 20.967100000000002 20.967100000000002 20.967100000000002