condition mean min max ZT0-3 329.864981 329.864981 329.864981 ZT4-7 341.595866 341.595866 341.595866 ZT8-11 328.9739605 328.9739605 328.9739605 ZT12-15 369.987511 369.987511 369.987511 ZT16-19 323.9400825 323.9400825 323.9400825 ZT20-23 283.0401465 283.0401465 283.0401465